Safety and Efficacy of High-Dose Daily Vitamin D3 Supplementation in Children and Young Adults Infected With Human Immunodeficiency Virus. Treatment of vitamin D depletion after Roux-en-Y gastric bypass: a randomized prospective clinical trial. Calcium and vitamin D intakes in children: a randomized controlled trial A Prospective Randomized Controlled Trial of the Effects of Vitamin D Supplementation on Cardiovascular Disease Risk Effect of weekly high-dose vitamin D3 supplementation on serum cholecalciferol concentrations in pregnant women High-dose vitamin D3 supplementation in a cohort of breastfeeding mothers and their infants: a 6-month follow-up pilot study. Vitamin D3 decreases parathyroid hormone in HIV-infected youth being treated with tenofovir: a randomized, placebo-controlled trial. Effect of isolated vitamin D supplementation on the rate of falls and postural balance in postmenopausal women fallers: a randomized, double-blind, placebo-controlled trial Impact of vitamin D supplementation during a resistance training intervention on body composition, muscle function, and glucose tolerance in overweight and obese adults. Effect of vitamin D supplementation alone on muscle function in postmenopausal women: a randomized, double-blind, placebo-controlled clinical trial Obstetric and neonatal outcomes of maternal vitamin D supplementation: results of an open-label, randomized controlled trial of antenatal vitamin D supplementation in Pakistani women. Improvements in peripheral vascular function with vitamin D treatment in deficient adolescents with type 1 diabetes Vitamin D Decreases Serum VEGF Correlating with Clinical Improvement in Vitamin D-Deficient Women with PCOS: A Randomized Placebo-Controlled Trial Serum magnesium and not vitamin D is associated with better QoL in COPD: A cross-sectional study. Vitamin d and physical activity status: associations with five-year changes in body composition and muscle function in community-dwelling older adults. Vitamin D intake to attain a desired serum 25-hydroxyvitamin D concentration. Vitamin D status affects strength gains in older adults supplemented with a combination of β-hydroxy-β-methylbutyrate, arginine, and lysine: a cohort study. L-arginine and Vitamin D Adjunctive Therapies in Pulmonary Tuberculosis: A Randomised, Double-Blind, Placebo-Controlled Trial Vitamin D Status and Impact of Vitamin D3 and/or Calcium Supplementation in a Randomized Pilot Study in the Southeastern United States Supplements of 20 microg/d cholecalciferol optimized serum 25-hydroxyvitamin D concentrations in 80% of premenopausal women in winter. Randomized controlled trial (RCT) of vitamin D supplementation in pregnancy in a population with endemic vitamin D deficiency. Vitamin D Status Relates to Reproductive Outcome in Women With Polycystic Ovary Syndrome: Secondary Analysis of a Multicenter Randomized Controlled Trial. Serum 25-hydroxyvitamin D response to vitamin D3 supplementation 50,000 IU monthly in youth with HIV-1 infection. Randomized trial of fortified milk and supplements to raise 25-hydroxyvitamin D concentrations in schoolchildren in Mongolia. Effects of Vitamin D Supplementation on Bone Mineral Density and Bone Markers in HIV-Infected Youth Prospective study of vitamin D supplementation and rickets in China. Role of Vitamin D in Insulin Secretion and Insulin Sensitivity for Glucose Homeostasis Pretreatment vitamin D level and response to neoadjuvant chemotherapy in women with breast cancer on the I-SPY trial (CALGB 150007/150015/ACRIN6657) Comparison of daily, weekly, and monthly vitamin D3 in ethanol dosing protocols for two months in elderly hip fracture patients. Efficacy of daily and monthly high-dose calciferol in vitamin D-deficient nulliparous and lactating women. Long-term vitamin D3 supplementation is more effective than vitamin D2 in maintaining serum 25-hydroxyvitamin D status over the winter months. Maternal vitamin D₃ supplementation at 50 μg/d protects against low serum 25-hydroxyvitamin D in infants at 8 wk of age: a randomized controlled trial of 3 doses of vitamin D beginning in gestation and continued in lactation. Daily supplementation with 15 μg vitamin D2 compared with vitamin D3 to increase wintertime 25-hydroxyvitamin D status in healthy South Asian and white European women: a 12-wk randomized, placebo-controlled food-fortification trial. Serum 25-Hydroxyvitamin D and the Incidence of Acute Viral Respiratory Tract Infections in Healthy Adults Vitamin D supplementation during Antarctic winter. Bone mineral content and serum 25-hydroxyvitamin D concentration in breast-fed infants with and without supplemental vitamin D. Effect of Low-Dose Vitamin D Supplementation on Serum 25(OH)D in School Children and White-Collar Workers Vitamin D supplementation in breastfed infants from Montréal, Canada: 25-hydroxyvitamin D and bone health effects from a follow-up study at 3 years of age How Much Vitamin D3 Do the Elderly Need? Vitamin D supplementation reduces insulin resistance in South Asian women living in New Zealand who are insulin resistant and vitamin D deficient - a randomised, placebo-controlled trial. Dose response to vitamin D supplementation in African Americans: results of a 4-arm, randomized, placebo-controlled trial. High-dose oral vitamin D3 supplementation in the elderly 25-hydroxyvitamin D accumulation during summer in elderly women at latitude 60 degrees N. Vitamin D: do we get enough? Randomized controlled trials of vitamin D and cancer incidence: A modeling study Effect of combined maternal and infant vitamin D supplementation on vitamin D status of exclusively breastfed infants. Effect of vitamin D supplementation on bone and vitamin D status among Pakistani immigrants in Denmark: a randomised double-blinded placebo-controlled intervention study. Estimation of the dietary requirement for vitamin D in healthy adults. Maternal-infant vitamin D relationships during breast-feeding. Maternal vitamin D supplementation to improve the vitamin D status of breast-fed infants: a randomized controlled trial. Vitamin D prophylaxis during infancy: comparison of the long-term effects of three intermittent doses (15, 5, or 2.5 mg) on 25-hydroxyvitamin D concentrations. Effect of Bimonthly Supplementation With Oral Cholecalciferol on Serum 25-Hydroxyvitamin D Concentrations in HIV-Infected Children and Adolescents Estimation of the dietary requirement for vitamin D in healthy adolescent white girls. Maintenance vitamin D3 dosage requirements in Chinese women with post menopausal osteoporosis living in the tropics. The effects of vitamin D3 supplementation on serum total 25[OH]D concentration and physical performance: a randomised dose–response study Gestational Age and Maternal Serum 25-hydroxyvitamin D Concentration Interact to Affect the 24,25-dihydroxyvitamin D Concentration in Pregnant Adolescents. Vitamin D supplementation in elderly nursing home residents increases 25(OH)D but not 1,25(OH)2D. Vitamin D supplementation in the prevention and management of major chronic diseases not related to mineral homeostasis in adults: research for evidence and a scientific statement from the European society for clinical and economic aspects of osteoporosis and osteoarthritis (ESCEO) Effect of oral cholecalciferol 2,000 versus 5,000 IU on serum vitamin D, PTH, bone and muscle strength in patients with vitamin D deficiency The impact of 1-year vitamin D supplementation on vitamin D status in athletes: a dose–response study Effect of vitamin D replacement on indexes of insulin resistance in overweight elderly individuals: a randomized controlled trial. Effect of different dosages of oral vitamin D supplementation on vitamin D status in healthy, breastfed infants: a randomized trial. Bread fortified with cholecalciferol increases the serum 25-hydroxyvitamin D concentration in women as effectively as a cholecalciferol supplement. Serum Vitamin D levels and Vitamin D supplementation do not correlate with the severity of chronic eczema in children. Effect of Vitamin D3 Supplementation in Black and in White Children: A Randomized, Placebo-Controlled Trial. A randomized controlled trial of vitamin D supplementation on perinatal depression: in Iranian pregnant mothers A 16-week randomized clinical trial of 2000 international units daily vitamin D3 supplementation in black youth: 25-hydroxyvitamin D, adiposity, and arterial stiffness. Very High-dose Cholecalciferol and Arteriovenous Fistula Maturation in ESRD: A Randomized, Double-blind, Placebo-Controlled Pilot Study Dose Response to Vitamin D Supplementation in Postmenopausal Women Randomized placebo-controlled trial of high-dose prenatal third-trimester vitamin D3 supplementation in Bangladesh: the AViDD trial Minimum Required Vitamin D Level for Optimal Increase in Bone Mineral Density with Alendronate Treatment in Osteoporotic Women Estimation of the dietary requirement for vitamin D in adolescents aged 14-18 y: a dose-response, double-blind, randomized placebo-controlled trial. Vitamin D requirement in pregnancy to prevent deficiency in neonates: a randomised trial. Vitamin D During Pregnancy and Infancy and Infant Serum 25-Hydroxyvitamin D Concentration Vitamin D requirements during lactation: high-dose maternal supplementation as therapy to prevent hypovitaminosis D for both the mother and the nursing infant. Hormonal Contraceptive Use Is Associated With Higher Total but Unaltered Free 25-Hydroxyvitamin D Serum Concentrations A Randomized, Double-Blind, Parallel Study to Evaluate the Dose-Response of Three Different Vitamin D Treatment Schemes on the 25-Hydroxyvitamin D Serum Concentration in Patients with Vitamin D Deficiency Recruitment and results of a pilot trial of vitamin D supplementation in the general population of Australia. Vitamin D3 Supplementation During Pregnancy and Lactation Improves Vitamin D Status of the Mother–Infant Dyad Relationship between the effect of eldecalcitol and serum 25(OH)D level Environmental, personal, and genetic determinants of response to vitamin D supplementation in older adults. Association of serum 25-hydroxyvitamin D with the risk of death in a general older population in Finland Cognition and Vitamin D in Older African‐American Women– Physical performance and Osteoporosis prevention with vitamin D in older African Americans Trial and Dementia Low serum 25-hydroxyvitamin D is associated with increased risk of stress fracture during Royal Marine recruit training Vitamin D supplementation and growth in urban Mongol school children: Results from two randomized clinical trials Cholecalciferol supplementation does not influence β-cell function and insulin action in obese adolescents: a prospective double-blind randomized trial. Pilot Study Evaluating Efficacy of 2 Regimens for Hypovitaminosis D Repletion in Pediatric Inflammatory Bowel Disease The effect of monthly 50 000 IU or 100 000 IU vitamin D supplements on vitamin D status in premenopausal Middle Eastern women living in Auckland Vitamin A to prevent bronchopulmonary dysplasia in very-low-birth-weight infants: has the dose been too low? The NICHD Neonatal Research Network. Cholecalciferol supplementation throughout winter does not affect markers of bone turnover in healthy young and elderly adults. Effect of moderate-dose vitamin D supplementation on insulin sensitivity in vitamin D-deficient non-Western immigrants in the Netherlands: a randomized placebo-controlled trial. Higher 1,25-dihydroxyvitamin D3 concentrations associated with lower fall rates in older community-dwelling women Vitamin D for health: a global perspective. Rationale and Design of Khuzestan Vitamin D Deficiency Screening Program in Pregnancy: A Stratified Randomized Vitamin D Supplementation Controlled Trial Long-term effects of nutrient intervention on markers of bone remodeling and calciotropic hormones in late-postmenopausal women. Optimal vitamin D status: a critical analysis on the basis of evidence-based medicine. High-dose vitamin d intervention in infants--effects on vitamin d status, calcium homeostasis, and bone strength. Vitamin D supplementation increases calcium absorption without a threshold effect. Increased vitamin D intake differentiated according to skin color is needed to meet requirements in young Swedish children during winter: a double-blind randomized clinical trial. Vitamin D Supplementation and Physical Performance in Adolescent Swimmers. A COMPARISON OF SERUM LEVELS OF 25-HYDROXY VITAMIN D IN PREGNANT WOMEN AT RISK FOR GESTATIONAL DIABETES MELLITUS AND WOMEN WITHOUT RISK FACTORS Annual high-dose vitamin D3 and mental well-being: randomised controlled trial. Effect of supplementation with cholecalciferol and calcium on 2-y bone mass accrual in HIV-infected children and adolescents: a randomized clinical trial. Vitamin D supplementation in pregnancy and lactation to promote infant growth Efficient tetanus toxoid immunization on vitamin D supplementation Estimation of the dietary requirement for vitamin D in free-living adults >=64 y of age. Influence of a single oral dose of vitamin D(2) on serum 25-hydroxyvitamin D concentrations in tuberculosis patients. Low vitamin D levels are associated with symptoms of depression in young adult males Vitamin D supplementation and CD4 count in children infected with human immunodeficiency virus. Impact of dietary and lifestyle on vitamin D in healthy student girls aged 11-15 years. Maternal vitamin D sufficiency and reduced placental gene expression in angiogenic biomarkers related to comorbidities of pregnancy Serum concentrations of 1,25-dihydroxyvitamin D2 and 1,25-dihydroxyvitamin D3 in response to vitamin D2 and vitamin D3 supplementation. The effect of high-dose vitamin D supplementation on serum vitamin D levels and milk calcium concentration in lactating women and their infants. Fortification of orange juice with vitamin D(2) or vitamin D(3) is as effective as an oral supplement in maintaining vitamin D status in adults. Estimations of Dietary Vitamin D Requirements in Black and White Children A Double-Blind, Placebo Controlled, Randomized Trial to Assess the Impact of a Monthly Administration of 50,000 IU of Vitamin D3 for 6 Months on Serum Levels of 25-Hydroxyvitamin D in Healthy Young Adults Large Doses of Vitamin D Fail to Increase 25-Hydroxyvitamin D Levels or to Alter Cardiovascular Risk Factors in Obese Adolescents: A Pilot Study. Lack of effect of subtherapeutic vitamin D treatment on glycemic and lipid parameters in Type 2 diabetes: A pilot prospective randomized trial. Response to Antenatal Cholecalciferol Supplementation Is Associated With Common Vitamin D–Related Genetic Variants Randomized controlled trial of vitamin D supplement on endothelial function in patients with type 2 diabetes. The inverse association between serum 25-hydroxyvitamin D and mortality may be modified by vitamin A status and use of vitamin A supplements Evaluation of Vitamin D Supplementation Doses during Pregnancy in a Population at High Risk for Deficiency Effect of vitamin D supplement on depression scores in people with low levels of serum 25-hydroxyvitamin D: nested case-control study and randomised clinical trial. Vitamin D fortification of growing up milk prevents decrease of serum 25-hydroxyvitamin D concentrations during winter: a clinical intervention study in Germany Efficacy and safety of vitamin D3 intake exceeding the lowest observed adverse effect level. The tolerability and biochemical effects of high‐dose bolus vitamin D2 and D3 supplementation in patients with vitamin D insufficiency
BACKGROUND Suboptimal vitamin D ( vitD ) status is common in children and young adults infected with human immunodeficiency virus ( HIV ) . The vitD supplemental dose needed to normalize vitD status in this population is unknown . METHODS In this double-blind trial , subjects infected with HIV ages 8.3 to 24.9 years were r and omized to vitD3 supplementation of 4000 IU/day or 7000 IU/day and evaluated at 6 and 12 week for changes in vitD status and HIV indicators . A dose was considered unsafe if serum calcium was elevated ( above age and sex-specific range ) associated with elevated serum 25 hydroxyvitamin D ( 25(OH)D ) ; > 160 ng/mL ) . RESULTS At baseline , 95 % of subjects ( n = 44 ; 43 % with perinatally acquired HIV , 57 % with behaviorally acquired HIV ) had a  suboptimal serum 25(OH)D concentration of < 32 ng/mL ( mean ± st and ard deviation , 19.3 ± 7.4 ; range , 4.4 - 33.6 ng/mL ) . After 12 weeks ( main outcome ) of D3 supplementation , both D3 doses were safe and well tolerated , with no evidence of elevation of serum calcium concentrations or deterioration in HIV immunologic or virologic status . Sufficient vitD status , defined as serum 25(OH)D ≥32 ng/mL , was achieved in 81 % of all subjects , and only the 7000 IU/day group ( 86 % ) achieved this a priori efficacy criterion in > 80 % of subjects . Change in serum 25(OH)D did not differ between HIV acquisition groups . CONCLUSIONS A 7000 IU/day D3 supplementation was safe and effective in children and young adults infected with HIV BACKGROUND A high prevalence ( 60 % ) of vitamin D ( VitD ) depletion , defined as a serum 25-hydroxyvitamin D level of < or = 20 ng/mL , is present in preoperative morbidly obese patients . Despite daily supplementation with 800 IU VitD and 1500 mg calcium after Roux-en-Y gastric bypass ( RYGB ) , VitD depletion persists in almost one half ( 44 % ) of patients . However , the optimal management of VitD depletion after RYGB and the potential benefits of such treatment are currently unknown . METHODS A total of 60 VitD-depleted morbidly obese women were r and omly assigned to receive 50,000 IU of VitD weekly after RYGB ( group 1 ; n = 30 ) or no additional VitD after RYGB ( group 2 ; n = 30 ) . All patients received a daily supplement of 800 IU VitD and 1500 mg calcium . The serum calcium , parathyroid hormone , 25-hydroxyvitamin D , bone-specific alkaline phosphatase , urinary N-telopeptide , and bone mineral density were measured preoperatively and 1 year after RYGB . Question naires were used to assess other potential sources of VitD , including sunlight exposure and ingestion of VitD-containing foods/liquids . RESULTS At 1 year after RYGB , VitD depletion and mean 25-hydroxyvitamin D level had improved significantly in group 1 ( 14 % and 37.8 ng/mL , respectively ) compared with the values in group 2 ( 85 % and 15.2 ng/mL , respectively ; P < .001 for both ) . A significant 33 % retardation in hip bone mineral density decline ( P = .043 ) and a significantly greater resolution of hypertension was seen in group 1 ( 75 % versus 32 % ; P = .029 ) . No significant adverse effects were encountered from pharmacologic VitD therapy . CONCLUSION The results of our study have shown that 50,000 IU of VitD weekly after RYGB safely corrects VitD depletion in most women , attenuates cortical bone loss , and improves resolution of hypertension Background Calcium ( Ca2 + ) and vitamin D ( VitD ) play an important role in child health . We evaluated the daily intake of Ca2 + and VitD in healthy children . Moreover , we demonstrate the efficacy of Ca2 + and VitD supplementation . Methods Daily Ca2 + and VitD intake was evaluated in consecutive healthy children through a vali date d question naire . Subjects with < 70 % of dietary reference intakes ( DRIs ) of Ca2 + and VitD were invited to participate in a prospect i ve r and omized trial with 2 groups of nutritional intervention : Group 1 , dietary counseling aim ing to optimize daily Ca2 + and VitD intake plus administration of a commercially available Ca2 + and VitD supplementation product ; Group 2 , dietary counseling alone . At the enrollment ( T0 ) and after 4 months ( T1 ) serum 25(OH ) Vitamin D levels were assessed . Results We evaluated 150 healthy children ( male 50 % , mean age 10 years ) ; at baseline a  low VitD intake  was observed in all subjects ( median 0.79 μg/die , IQR 1.78 ; range 0.01 - 5.02 ) ; this condition was associated with Ca2 + intake < 70 % of the DRIs in 82 subjects ( 55 % ) . At baseline serum 25(OH)D levels were low ( < 30 ng/ml ) in all study subjects and after 4 months of nutritional intervention , a normalization of serum 25(OH)D levels ( ≥30 ng/ml ) was observed in all children in Group 1 and in only one subject in Group 2 [ Group 1 : T1 33.8 ng/ml ( IQR 2.5 ) vs Group 2 : T1 24.5 ng/ml ( IQR 5.2 ) , p < 0.001 ] . Conclusions Adequate Ca2 + and VitD intakes are difficult to obtain through dietary counseling alone in pediatric subjects . Oral supplementation with of Ca2 + and VitD is a reliable strategy to prevent this condition . Trial registration The study was registered in Clinical Trials Protocol Registration System ( ID number : NCT01638494 ) Vitamin D ( VitD ) supplementation has been advocated for cardiovascular risk reduction ; however , supporting data are sparse . The objective of this study was to determine whether VitD supplementation reduces cardiovascular risk . Subjects in this prospect i ve , r and omized , double-blind , placebo-controlled trial of post-menopausal women with serum 25-hydroxyvitamin D concentrations > 10 and < 60 ng/mL were r and omized to Vitamin D3 2500 IU or placebo , daily for 4 months . Primary endpoints were changes in brachial artery flow-mediated vasodilation ( FMD ) , carotid-femoral pulse wave velocity ( PWV ) , and aortic augmentation index ( AIx ) . The 114 subjects were mean ( st and ard deviation ) 63.9 ( 3.0 ) years old with a 25-hydroxyvitamin D level of 31.3 ( 10.6 ) ng/mL.  Low VitD ( < 30 ng/mL ) was present in 47 % and was associated with higher body-mass index , systolic blood pressure , glucose , CRP , and lower FMD ( all p<0.05 ) . After 4 months , 25-hydroxyvitamin D levels increased by 15.7 ( 9.3 ) ng/mL on vitamin D3 vs. −0.2 ( 6.1 ) ng/mL on placebo ( p<0.001 ) . There were no significant differences between groups in changes in FMD ( 0.3 [ 3.4 ] vs. 0.3 [ 2.6 ] % , p = 0.77 ) , PWV ( 0.00 [ 1.06 ] vs. 0.05 [ 0.92 ] m/s , p = 0.65 ) , AIx ( 2.7 [ 6.3 ] vs. 0.9 [ 5.6 ] % , p = 0.10 ) , or CRP ( 0.3 [ 1.9 ] vs. 0.3 [ 4.2 ] mg/L , p = 0.97 ) . Multivariable models showed no significant interactions between treatment group and low VitD status ( < 30 ng/mL ) for changes in FMD ( p = 0.65 ) , PWV ( p = 0.93 ) , AIx ( p = 0.97 ) , or CRP ( p = 0.26).In conclusion , VitD supplementation  did not improve endothelial function , arterial stiffness , or inflammation . These observations do not support use of VitD supplementation to reduce cardiovascular disease risk . Trial Registration Clinical Trials.gov NCT00690417 Trial Registration Clinical Trials.gov Vitamin D status is conventionally defined by the serum concentration of 25-hydroxyvitamin D. However , it has been proposed that the serum cholecalciferol concentration ( D3 ) also determines functional vitamin D sufficiency . The objective of this study was to describe the effect of weekly high-dose vitamin D3 supplementation on inter-dose serum D3 in pregnant women . We conducted a sub- study of a completed r and omized double-blind placebo-controlled trial of vitamin D3 ( 35,000 IU/week ) supplementation in late pregnancy ( AViDD trial ) in Dhaka , Bangladesh . This study included pregnant women enrolled at 26 - 29 weeks gestation who fully adhered to the prenatal supplement intervention for ≥8 consecutive weeks and for whom serum sample s were available for D3 analysis ( n=65 ) . Serum D3 was uniformly low at enrolment . Mean D3 increased and was maximal at 1 day after vitamin D dose administration ( 152.09nmol/L , SD 25.11nmol/L ) and remained significantly higher in VitD vs. Pl at 7 days ( 29.59nmol/L vs. 1.92nmol/L , p=0.007 ) . Daily average of the group mean D3 during the week following dosing was 66.97nmol/L in VitD versus 2.13nmol/L in Pl . In conclusion , serum D3 remained significantly elevated throughout the week following ≥8 consecutive weekly doses of 35,000 IU D3 in pregnant women . However , the clinical ly significant minimum threshold of serum D3 remains to be established OBJECTIVE To examine the effect of high-dose maternal vitamin D(3 ) ( vitD ) supplementation on the nutritional vitD status of breastfeeding ( BF ) women and their infants compared with maternal and infant controls receiving 400 and 300 IU vitD/day , respectively . DESIGN Fully lactating women ( n = 19 ) were enrolled at 1-month postpartum into a r and omized- control pilot trial . Each mother received one of two treatments for a 6-month study period : 0 or 6000 IU vitD(3 ) plus a prenatal vitamin containing 400 IU vitD(3 ) . The infants of mothers assigned to the control group received 300 IU vitD(3)/day ; those infants of mothers in the high-dose group received 0 IU ( placebo ) . Maternal serum and milk vitD and 25(OH)D were measured at baseline then monthly ; infant serum vitD and 25(OH)D were measured at baseline , and months 4 and 7 . Urinary calcium/creatinine ratios were measured monthly in both mothers and infants . Dietary and BF history and outdoor activity question naires were completed at each visit . Changes in skin pigmentation were measured by spectrophotometry . Data were analyzed using chi-square , t-test , and analysis of variance ( ANOVA ) on an intent-to-treat basis . RESULTS High-dose ( 6400 IU/day ) vitD(3 ) safely and significantly increased maternal circulating 25(OH)D and vitD from baseline compared to controls ( p < 0.0028 and 0.0043 , respectively ) . Mean milk antirachitic activity of mothers receiving 400 IU vitD/day decreased to a nadir of 45.6 at visit four and varied little during the study period ( 45.6 - 78.6 IU/L ) , whereas the mean activity in the 6400 IU/day group increased from 82 to 873 IU/L ( p < 0.0003 ) . There were no differences in circulating 25(OH)D levels of infants supplemented with oral vitD versus infants whose only source of vitD was breast milk . CONCLUSION With limited sun exposure , an intake of 400 IU/day vitamin D(3 ) did not sustain circulating maternal 25(OH)D levels , and thus , supplied only extremely limited amounts of vitamin D to the nursing infant via breast milk . Infant levels achieved exclusively through maternal supplementation were equivalent to levels in infants who received oral vitamin D supplementation . Thus , a maternal intake of 6400 IU/day vitamin D elevated circulating 25(OH)D in both mother and nursing infant BACKGROUND The study goal was to determine the effect of vitamin D ( VITD ) supplementation on tubular reabsorption of phosphate ( TRP ) , parathyroid hormone ( PTH ) , bone alkaline phosphatase ( BAP ) , and C-telopeptide ( CTX ) in youth infected with human immunodeficiency virus ( HIV ) receiving and not receiving combination antiretroviral therapy ( cART ) containing tenofovir disoproxil fumarate ( TDF ) . METHODS This r and omized , double-blind , placebo-controlled multicenter trial enrolled HIV-infected youth 18 - 25 years based on stable treatment with cART containing TDF ( n = 118 ) or no TDF ( noTDF ; n = 85 ) , and r and omized within those groups to vitamin D3 , 50 000 IU ( n = 102 ) or placebo ( n = 101 ) , administered at 0 , 4 , and 8 weeks . Outcomes included change in TRP , PTH , BAP , and CTX from baseline to week 12 by TDF/noTDF ; and VITD/placebo . RESULTS At baseline , VITD and placebo groups were similar except those on TDF had lower TRP and higher PTH and CTX . At week 12 , 95 % in the VITD group had sufficient serum 25-hydroxy vitamin D ( 25-OHD ; ≥20 ng/mL ) , increased from 48 % at baseline , without change in placebo ( P < .001 ) . PTH decreased in the TDF group receiving VITD ( P = .031 ) but not in the noTDF group receiving VITD , or either placebo group . The decrease  in  PTH with VITD in those on TDF occurred with insufficient and sufficient baseline 25-OHD ( mean PTH change , -7.9 and -6.2 pg/mL ; P = .031 and .053 , respectively ) . CONCLUSIONS In youth on TDF  , vitamin D3 supplementation decreased PTH , regardless of baseline 25-OHD concentration . CLINICAL TRIALS REGISTRATION NCT00490412 Objective : To evaluate the effect of isolated vitamin D supplementation ( VITD ) on the rate of falls and postural balance in postmenopausal women fallers . Methods : In this double-blind , placebo-controlled trial , 160 Brazilian younger postmenopausal women were r and omized into two groups : VITD group , vitamin D3 supplementation 1,000 IU/day/orally ( n = 80 ) and placebo group ( n = 80 ) . Women with amenorrhea at least 12 months , age 50 to 65 years , and a history of falls ( previous 12 months ) were included . Those with neurological or musculoskeletal disorders , vestibulopathies , drugs use that could affect balance and osteoporosis were excluded . The intervention time was 9 months . Postural balance was assessed by stabilometry ( computerized force platform ) and investigation on the occurrence/recurrence of falls was performed by interviews . The plasma concentration of 25-hydroxyvitamin D [ 25(OH)D ] was measured by high-performance liquid chromatography . Statistical analysis was achieved by intention-to-treat , using analysis of variance , Student 's t test , Tukey test , chi-square , and logistic regression . Results : After 9 months , mean values of 25(OH)D increased from 15.0 ± 7.5 ng/mL to 27.5 ± 10.4 ng/mL ( + 45.4 % ) in the VITD group , and decreased from 16.9 ± 6.7 ng/mL to 13.8 ± 6.0 ng/mL ( −18.5 % ) in the placebo group ( P < 0.001 ) . The occurrence of falls was higher in the placebo group ( + 46.3 % ) with an adjusted risk of 1.95 ( 95 % confidence interval [ CI ] 1.23 - 3.08 ) times more likely to fall and 2.80 ( 95 % CI 1.43 - 5.50 ) times higher for recurrent falls compared to the VITD group ( P < 0.001 ) . There was reduction in body sway by stabilometry , with lower amplitude of antero-posterior ( −35.5 % ) and latero-lateral ( −37.0 % ) oscillation , only in the VITD group ( P < 0.001 ) . Conclusions : In Brazilian postmenopausal women fallers  , isolated vitamin D supplementation for 9 months result ed in a lower incidence of falls and improvement in postural balance BACKGROUND & AIMS The impact of vitamin D supplementation in overweight and obese adults during resistance training on body composition , muscle function , and glucose tolerance was investigated . METHODS Twenty-three overweight and obese ( age : 26.1±4.7 y ; BMI : 31.3±3.2 kg/m(2 ) ; 25-hydroxyvitamin D : 19.3±7.2 ng/mL ) adults were recruited for participation in a double-blind , placebo-controlled trial . Participants were r and omly divided into vitamin D ( VitD , 4000 IU/d ; 5 females , 5 males ) and placebo ( PL ; 7 females , 6 males ) groups . Both groups completed 12 weeks of resistance training . 25-hydroxyvitamin D , parathyroid hormone , body composition , and glucose tolerance were assessed at baseline and 12 weeks . Muscle function ( strength and power ) was assessed at baseline , 4 , 8 , and 12 weeks . RESULTS During the intervention , 25-hydroxyvitamin D increased and parathyroid hormone decreased in the VitD group ( P<0.05 ) . Peak power was significantly increased at 4 weeks in the VitD group only ( P<0.05 ) . Regression analysis revealed an inverse association between the change in 25-hydroxyvitamin D with the change in waist-to-hip ratio ( R(2)=0.205 , P=0.02 ) . No other improvements were observed with supplementation . CONCLUSIONS Vitamin D supplementation in overweight and obese adults during resistance training induced an early improvement in peak power , and elevated vitamin D status was associated with reduced waist-to-hip ratio . CLINICAL TRIAL REGISTRATION NUMBER NCT01199926 Summary The present study investigates the effects of vitamin D on muscle function in postmenopausal women . It has been shown that vitamin D supplementation in postmenopausal women with hypovitaminosis D provides significant protective factor against sarcopenia , with significant increases in muscle strength and control of progressive loss of lean mass . Introduction We aim ed to evaluate the effect of supplementation of vitamin D ( VITD ) alone on muscle function in younger postmenopausal women . Methods In this double-blind , placebo-controlled clinical trial , 160 Brazilian postmenopausal women were r and omized into two groups : VITD group consisting of patients receiving vitamin D3 1000 IU/day orally ( n = 80 ) or placebo group ( n = 80 ) . Women with amenorrhea for more than 12 months and age 50–65 years , with a history of falls ( previous 12 months ) , were included . The intervention time was 9 months , with assessment s at two points , start and end . Lean mass was estimated by total-body dual-energy X-ray absorptiometry ( DXA ) and muscle strength by h and grip strength and chair rising test . The plasma concentrations of 25-hydroxyvitamin D [ 25(OH)D ] were measured by high-performance liquid chromatography ( HPLC ) . Statistical analysis was by intention to treat ( ITT ) , using ANOVA , Student ’s t test , and Tukey ’s test . Results After 9 months , average values of 25(OH)D increased from 15.0 ± 7.5 to 27.5 ± 10.4 ng/ml ( + 45.4 % ) in the VITD group and decreased from 16.9 ± 6.7 to 13.8 ± 6.0 ng/ml ( −18.5 % ) in the placebo group ( p < 0.001 ) . In the VITD group , there was significant increase in muscle strength ( + 25.3 % ) of the lower limbs by chair rising test ( p = 0.036 ) . In women in the placebo group , there was considerable loss ( −6.8 % ) in the lean mass ( p = 0.030 ) . Conclusion The supplementation of vitamin D alone in postmenopausal women provided significant protective factor against the occurrence of sarcopenia , with significant increases in muscle strength and control of progressive loss of lean mass OBJECTIVE The objective of the study was to determine whether vitamin D ( vitD ) supplementation during pregnancy affects obstetric and neonatal outcomes . SETTING The study was conducted at a university hospital in Karachi , Pakistan . METHODS The study was a single-center , open-label , r and omized , controlled trial of routine care ( group A , 200 mg ferrous sulfate and 600 mg calcium daily ) vs vitD supplementation ( group B , 4000 IU vitamin D3 daily ) , started at 20 weeks and continued till delivery . Maternal serum sample s of 25-hydroxyvitamin D ( 25OHD ) were collected at baseline and delivery . Neonatal vitD status was assessed in cord blood or in neonatal serum sample s within 48 hours of birth . Obstetric outcomes included gestational hypertension , gestational diabetes , and preterm labor , and neonatal well-being included small for gestational age , birth weight , length , head circumference , and 1- and 5-minute Apgar scores . RESULTS Of 207 gravidae enrolled , 193 completed the trial .  Maternal age , vitD status , and gestational age at enrollment were comparable between the two groups . At delivery , maternal 25OHD was increased in group B ( 18.3 ± 11 ng/dL vs 8.82 ± 11.84 ng/dL ( P = .001 ) compared with group A ( 6.9 ± 7.0 ng/dL vs 6.32 ± 3.97 ng/dL , P = .06 ) . The obstetric outcomes were comparable between the two groups ( P > .05 ) . Neonatal 25OHD levels were significantly higher in group B compared with group A ( 19.22 ± 12.19 ng/dL vs 6.27 ± 5.2 ng/dL ) . There was positive correlation between maternal and neonatal 25OHD levels ( r = 0.83 , P = .001 ) . One- and 5-minute Apgar scores were significantly higher in group B ( 7.10 ± 0.66 vs 6.90 ± 0.50 , P = .026 , and 8.53 ± 0.68 vs 8.33 ± 0.81 , P = .051 , respectively ) . Neonatal anthropometric parameters were comparable between the two groups ( P > .05 ) . CONCLUSION Maternal vitD supplementation improved maternal and neonatal vitD status BACKGROUND Vitamin D ( VitD ) deficiency is prevalent in adolescents with type 1 diabetes ( T1D ) and is associated with diabetes-related vascular complications in adulthood . The objective of this clinical trial was to assess VitD treatment on endothelial function ( EF ) and markers of renal inflammation , in this patient group . METHODS Adolescents with T1D with suboptimal levels of VitD ( < 37.5 nmol/L ) were treated for 12 to 24 weeks with a VitD analog ( VitD3 ) at doses of 1000 or 2000 IU daily . The primary end-point assessed the change in reactive hyperemia index ( lnRHI ) , a measure of EF . Secondary end-points included changes in blood pressure , lipid profile , HbA1c and albumin creatinine ratio ( ACR ) . Urinary cytokine/chemokine inflammatory profile was also assessed in a subset of subjects posttreatment . RESULTS Two hundred and seventy-one subjects were screened for VitD status and 31 VitD deficient subjects with a mean age of 15.7 ± 1.4 years were enrolled and completed the study . Mean 25-OH-VitD levels significantly increased ( 33.0 ± 12.8 vs 67.0 ± 23.2 nmol/L , P < .01 ) with a significant improvement in EF  following VitD supplementation ( lnRHI 0.58 ± 0.20 vs 0.68 ± 0.21 , P = .03 ) . VitD supplementation did not significantly impact systolic blood pressure/diastolic blood pressure ( SBP/DBP ) , lipids , HbA1c and ACR and no adverse effects were seen . Several urinary inflammatory cytokines/chemokines : MCP-3 ( P < .01 ) , epidermal growth factor ( EGF ) ( P < .01 ) tumor necrosis factor β ( TNFβ ) ( P = .01 ) , interleukin-10 ( IL-10 ) ( P = .01 ) , also significantly decreased post-VitD-treatment . CONCLUSIONS Treatment with VitD was associated with an improvement in EF and reduced expression of urinary inflammatory markers in adolescents with T1D . This data is suggestive of an additional benefit of VitD supplementation on early markers of microvascular complications Vascular endothelial growth factor ( VEGF ) has been suggested to play a role in the pathophysiology of polycystic ovary syndrome ( PCOS ) and may contribute to increased risk of ovarian hyperstimulation syndrome ( OHSS ) in affected individuals .  Vitamin D ( VitD ) supplementation improves multiple clinical parameters in VitD-deficient women with PCOS and decreases VEGF levels in several other pathologic conditions . Unveiling the basic mechanisms underlying the beneficial effects of vitamin D on PCOS may enhance our underst and ing of the pathophysiology of this syndrome . It may also suggest a new treatment for PCOS that can improve it through the same mechanism as vitamin D and can be given regardless of vitamin D levels . Therefore , we aim ed to explore the effect of VitD supplementation on serum VEGF levels and assess whether changes in VEGF correlate with an improvement in characteristic clinical abnormalities of PCOS . This is a r and omized placebo-controlled trial conducted between October 2013 and March 2015 . Sixty-eight VitD-deficient women with PCOS were recruited . Women received either 50,000 IU of oral VitD3 or placebo once weekly for 8 weeks . There was a significant decrease in serum VEGF levels ( 1106.4 ± 36.5 to 965.3 ± 42.7 pg·mL–1 ; p < 0.001 ) in the VitD group . Previously reported findings of this trial demonstrated a significant decrease in the intermenstrual intervals , Ferriman-Gallwey hirsutism score , and triglycerides  following VitD supplementation . Interestingly , ∆VEGF was positively correlated with ∆triglycerides ( R2 = 0.22 ; p = 0.02 ) following VitD supplementation . In conclusion , VitD replacement significantly decreases serum VEGF levels correlating with a decrease in triglycerides in women with PCOS . This is a novel molecular explanation for the beneficial effects of VitD treatment . It also suggests the need to investigate a potential role of VitD treatment in reducing the incidence or severity of OHSS in VitD-deficient women with PCOS BACKGROUND Deficiency of serum levels of vitamin D3 ( se vitD ) , magnesium ( se Mg ) and calcium ( se Ca ) may be associated with increased exacerbation risk in chronic obstructive pulmonary disease ( COPD ) . However , associations with other aspects of COPD , e.g. lung function and quality of life ( QoL ) , have been studied less extensively . AIM To investigate se vitD , se Mg and se Ca in COPD and their associations with both forced expiratory volume in 1st second ( FEV1 ) and QoL. METHODS  FEV1 and se vitD ( assessed by 25-(OH)-D3 ) , se Mg and se Ca were measured during summertime . Generic and health related QoL were characterized . RESULTS This cross-sectional study included 143 participants with COPD . Women had a significantly higher se vitD than men ( P = 0.0028 ) , and 27 % of participants were se vitD deficient . FEV1 was not correlated with se vitD , se Mg or se Ca in COPD . Mg deficiency group reported significantly impaired mobility , usual activities , pain/discomfort and COPD -related QoL.  Se vitD and se Ca were not associated with QoL. CONCLUSION Serum levels of vitD , Mg and Ca were not related to FEV1 . Most participants in this study were  vitD- , Mg- and Ca sufficient . Women had higher se vitD  than men . Se Mg , but not se vitD and se Ca , was associated with QoL in COPD . Prospect i ve r and omized studies are needed to substantiate these finding . Clinical trials ID at www . clinical trials.gov : NCT01564953 CONTEXT High vitamin D and physical activity ( PA ) levels are independently associated with improved body composition and muscle function in older adults . OBJECTIVE The objective of this study was to investigate the interaction of 25-hydroxyvitamin D ( 25OHD ) and PA status in maintenance of body composition and muscle function in older adults . DESIGN AND SETTING This was a 5-year prospect i ve population -based study of Australian community-dwelling older adults . PARTICIPANTS Participants in the study included 615 community-dwelling volunteers aged 50 years old or older [ 61.4 ± 6.9 ( mean ± SD ) y ; 48 % female ] r and omly selected from electoral rolls and categorized according to baseline serum 25OHD ( ≥ or < 50 nmol/L ) and PA ( ≥ or < 10,000 pedometer determined steps/d ) levels as follows : high 25OHD and high PA ( VitD+PA+ ) ; high 25OHD and low PA ( VitD+PA- ) ; low 25OHD and high PA ( VitD-PA+ ) ; and low 25OHD and low PA ( VitD-PA- ) . A subset of 518 participants completed accelerometer assessment s during follow-up . MAIN OUTCOME MEASURES Changes in dual-energy X-ray absorptiometry-assessed body composition and lower-limb muscle function were measured . RESULTS VitD+PA+ had significantly smaller increases in body fat over 5 years compared with other groups ( all P < .05 ) . Higher baseline pedometer-determined PA result ed in declines in total body fat ( β = -.23 kg per 100 steps/d , P = .001 ) over 5 years for participants with high 25OHD but not those with low 25OHD ( P > .05 ) . Among participants with accelerometer data , these associations were generally mediated by higher levels of moderate/vigorous PA . CONCLUSIONS High vitamin D status appears to enhance PA-related declines in body fat during aging , but the mechanism may be greater amounts of outdoor moderate/vigorous PA rather than a direct effect of 25OHD BACKGROUND Indirect evidence suggests that optimal vitamin D status is achieved with a serum 25-hydroxyvitamin D [ 25(OH)D ] concentration > 75 nmol/L. OBJECTIVE We aim ed to determine the intake of vitamin D(3 ) needed to raise serum 25(OH)D to > 75 nmol/L. DESIGN The design was a 6-mo , prospect i ve , r and omized , double-blinded , double-dummy , placebo-controlled study of vitamin D(3 ) supplementation .  Serum 25(OH)D was measured by  radioimmunoassay . Vitamin D(3 ) intake was adjusted every 2 mo by use of an algorithm based on serum 25(OH)D concentration . RESULTS A total of 138 subjects entered the study . After 2 dose adjustments , almost all active subjects attained concentrations of 25(OH)D > 75 nmol/L , and no subjects exceeded 220 nmol/L. The mean ( + /-SD ) slope at 9 wk [ defined as 25(OH)D change/baseline dose ] was 0.66 + /- 0.35 (nmol/L)/(microg/d ) and did not differ statistically between blacks and whites . The mean daily dose was 86 microg ( 3440 IU ) . The use of computer simulations to obtain the most participants within the range of 75 - 220 nmol/L predicted an optimal daily dose of 115 microg/d ( 4600 IU ) . No hypercalcemia or hypercalciuria was observed . CONCLUSIONS Determination of the intake required to attain serum 25(OH)D concentrations > 75 nmol/L must consider the wide variability in the dose-response curve and basal 25(OH)D concentrations . Projection of the dose-response curves observed in this convenience sample onto the population of the third National Health and Nutrition Examination Survey suggests a dose of 95 microg/d ( 3800 IU ) for those above a 25(OH)D threshold of 55 nmol/L and a dose of 125 microg/d ( 5000 IU ) for those below that threshold BACKGROUND Older adults supplemented for 1 year with β-hydroxy-β-methylbutyrate , arginine , and lysine ( HMB/ARG/LYS ) were previously shown to have significant gains in fat-free mass ( FFM ) but not muscular strength . OBJECTIVE Recently , increasing levels of serum vitamin D have been associated with an increase in muscle function , particularly in the elderly . To determine if vitamin D status may have limited strength gain in participants supplemented with HMB/ARG/LYS , the authors performed post hoc analysis of strength based on the participants ' vitamin D status . METHODS Elderly ( age 76.0 ± 1.6 years ) adults were recruited for a double-blinded , controlled study and were r and omly assigned to either an isonitrogenous control ( n = 37 ) or HMB/ARG/LYS ( n = 40 ) for the yearlong study . Participants were further segregated based on their vitamin D status of either < 30 or ≥30 ng 25OH-vitD(3)/mL serum , and an analysis was performed on the 4 cohorts . RESULTS Regardless of vitamin D status , HMB/ARG/LYS result ed in significantly increased FFM ( P < .02 ) , but only in those with vitamin D status ≥30 ng 25OH-vitD(3)/mL was there a significant increase in strength with HMB/ARG/LYS ( P < .01 ) . Control-supplemented participants , regardless of vitamin D status , and the HMB/ARG/LYS-supplemented participants with vitamin D status < 30 ng 25OH-vitD(3 ) failed to show improvements in strength . CONCLUSIONS The nutrient cocktail of HMB/ARG/LYS alone was effective in increasing muscle mass regardless of vitamin D status , but accompanying strength increases were observed only when participants also had adequate vitamin D status indicating a synergistic effect between the HMB/ARG/LYS and vitamin Background Vitamin D ( vitD ) and L-arginine have important antimycobacterial effects in humans . Adjunctive therapy with these agents has the potential to improve outcomes in active tuberculosis ( TB ) . Methods In a 4-arm r and omised , double-blind , placebo-controlled factorial trial in adults with smear-positive pulmonary tuberculosis ( PTB ) in Timika , Indonesia , we tested the effect of oral adjunctive vitD 50,000 IU 4-weekly or matching placebo , and L-arginine 6.0 g daily or matching placebo , for 8 weeks , on proportions of participants with negative 4-week sputum culture , and on an 8-week clinical score ( weight , FEV1 , cough , sputum , haemoptysis ) . All participants with available endpoints were included in analyses according to the study arm to which they were originally assigned . Adults with new smear-positive PTB were eligible . The trial was registered at Clinical Trials.gov NCT00677339 . Results 200 participants were enrolled , less than the intended sample size : 50 received L-arginine + active vitD , 49 received L-arginine + placebo vit D , 51 received placebo L-arginine + active vitD and 50 received placebo L-arginine + placebo vitD. According to the factorial model , 99 people received arginine , 101 placebo arginine , 101 vitamin D , 99 placebo vitamin D. Results for the primary endpoints were available in 155 ( 4-week culture ) and 167 ( clinical score ) participants . Sputum culture conversion was achieved by week 4 in 48/76 ( 63 % ) participants in the active L-arginine versus 48/79 ( 61 % ) in placebo L-arginine arms ( risk difference −3 % , 95 % CI −19 to 13 % ) , and in 44/75 ( 59 % ) in the active vitD versus 52/80 ( 65 % ) in the placebo vitD arms ( risk difference 7 % , 95 % CI −9 to 22 % ) . The mean clinical outcome score also did not differ between study arms . There were no effects of the interventions on adverse event rates including hypercalcaemia , or other secondary outcomes . Conclusion Neither vitD nor L-arginine supplementation , at the doses administered and with the power attained , affected TB outcomes . Registry Clinical Trials.gov . Registry number : Objective : Vitamin D supplementation may be required for certain subgroups in the United States in whom status and intake are inadequate , but the impact of various doses , and whether calcium administration jointly or independently influences vitamin D metabolite levels , is unclear . Methods : In a pilot chemoprevention trial of biomarkers of risk for colorectal adenoma , we measured the impact of vitamin D supplementation and /or calcium supplementation on plasma vitamin D metabolite concentrations . Ninety-two adult men and women living in the southeastern United States were r and omized to 800 IU vitamin D3 , 2000 mg elemental calcium , both , or placebo daily for 6 months . We examined vitamin D status at baseline and postintervention and compared the change in plasma 25-hydroxyvitamin D ( 25(OH)D ) and 1,25(OH)2D levels by intervention group using general linear models . Results : Eighty-two percent of the study population had insufficient plasma 25(OH)D concentrations ( < 75 nmol/L ) at baseline , with the lowest levels observed among African American participants . Vitamin D supplements , with or without calcium supplementation , raised plasma 25(OH)D concentrations , on average , by 25 to 26 nmol/L. Half of the study participants were classified as having sufficient 25(OH)D status after 6 months of 800 IU of vitamin D3 daily . Calcium alone did not influence 25(OH)D concentrations . Conclusion : In this southeastern U.S. population , half of the study participants receiving 800 IU vitamin D3 daily had blood 25(OH)D concentrations of ≤75 nmol/L after a 6-month intervention period , supporting higher vitamin D dose requirements estimated by some groups . More research is needed to identify the optimal vitamin D dose to improve 25(OH)D status in various at-risk population The serum 25-hydroxyvitamin D [ 25(OH)D ] response to daily supplementation with 20 microg cholecalciferol ( D3 ) during winter in predominantly white premenopausal women living in Maine was measured and the effects of body composition and hormonal contraceptive use on baseline serum 25(OH)D concentrations and the response to supplementation were examined . A total of 112 women ( 22.2 + /- 3.7 y old ) received placebo from March 2005 until September 2005 when they were r and omized to receive either placebo or 20 microg/d D3 through February 2006 . Eighty-six women completed the study .  Actual mean D3 content of the supplements was 22 microg per capsule . In February 2005 the serum 25(OH)D concentration was 62.0 + /- 23.4 nmol/L ( mean + /- SD ) . Serum 25(OH)D concentrations increased by 35.3 + /- 23.2 nmol/L from February 2005 to February 2006 in the treatment group , significantly more than the 10.9 + /- 16.9 nmol/L increase in the placebo group . Treatment group , magnitude of summer increase in 25(OH)D , estrogen dose , and baseline serum 25(OH)D concentrations , but not body fat , were significant predictors of the 1-y change in 25(OH)D concentrations used to assess the magnitude of the response to supplementation . Daily supplementation with 20 microg D3 during winter achieved optimal 25(OH)D concentrations ( > or = 75 nmol/L ) in 80 % of participants , indicating that this dose is adequate to optimize vitamin D status in most young women in Maine BACKGROUND Vitamin D ( vD ) deficiency in pregnancy is a global health problem and the amount of vD supplementation to prevent vD deficiency is controversial . OBJECTIVE The objective of the study was to determine effectiveness and safety of prenatal 2000 IU and 4000 IU/d compared with 400 IU/d vD3 supplementation in a r and omized controlled trial in population in which vD deficiency is endemic . DESIGN / METHODS Arab women were r and omized at 12 - 16 weeks of gestation to 400 , 2000 , and 4000 IU/d  vD3 , which were continued to delivery . Serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations were measured during pregnancy and at delivery . The primary outcome was the maternal and cord blood 25(OH)D , and the secondary outcomes were the achievement of sufficient serum 25(OH)D of 32 ng/mL or greater ( ≥80 nmol/L ) at delivery . SETTING The locations were primary care and tertiary perinatal care centers . RESULTS Of 192 enrolled , 162 ( 84 % ) continued to delivery . Mean serum 25(OH)D of 8.2 ng/mL ( 20.5 nmol/L ) at enrollment was low . Mean serum 25(OH)D concentrations at delivery and in cord blood were significantly higher in the 2000 and 4000 IU than the 400 IU/d group ( P < .001 ) and was highest in the 4000 IU/d group . The percent who achieved 25(OH)D greater than 32 ng/mL and greater than 20 ng/mL concentrations in mothers and infants was highest in 4000 IU/d group . Safety measurements were similar by group and no adverse event related to vD supplementation . CONCLUSIONS Vitamin D supplementation of 2000 and 4000 IU/d appeared safe in pregnancy , and 4000 IU/d was most effective in optimizing serum 25(OH)D concentrations in mothers and their infants . These findings could apply to other population s in which vD deficiency is endemic CONTEXT Experimental evidence supports a relevance of vitamin D ( VitD ) for reproduction ; however , data in humans are sparse and inconsistent . OBJECTIVE To assess the relationship of VitD status with ovulation induction ( OI ) outcomes in women with polycystic ovary syndrome ( PCOS ) . DESIGN A retrospective cohort . SETTING Secondary analysis of r and omized controlled trial data . PARTICIPANTS Participants in the Pregnancy in PCOS I ( PPCOS I ) r and omized controlled trial ( n = 540 ) met the National Institutes of Health diagnostic criteria for PCOS . INTERVENTIONS  Serum 25OHD levels were measured in stored sera . MAIN OUTCOME MEASURES Primary , live birth ( LB ) ; secondary , ovulation and pregnancy loss after OI . RESULTS Likelihood for LB was reduced by 44 % for women if the 25OHD level was < 30 ng/mL ( < 75 nmol/L ; odds ratio [ OR ] , 0.58 [ 0.35 - 0.92 ] ) . Progressive improvement in the odds for LB was noted at thresholds of ≥38 ng/mL ( ≥95 nmol/L ; OR , 1.42 [ 1.08 - 1.8 ] ) , ≥40 ng/mL ( ≥100 nmol/L ; OR , 1.51 [ 1.05 - 2.17 ] ) , and ≥45 ng/mL ( ≥112.5 nmol/L ; OR , 4.46 [ 1.27 - 15.72 ] ) . On adjusted analyses , VitD status was an independent predictor of LB and ovulation after OI . CONCLUSIONS In women with PCOS , serum 25OHD was an independent predictor of measures of reproductive success after OI . Our data identify reproductive thresholds for serum 25OHD that are higher than recommended for the nonpregnant population CONTEXT Vitamin D deficiency and insufficiency occur frequently in youth with HIV infection , particularly among those receiving the antiretroviral drug efavirenz . Optimal vitamin D dosing for treatment is unclear . OBJECTIVE Our objective was to evaluate safety and measure change in 25-hydroxyvitamin D ( 25-OHD ) concentration from baseline to study wk 4 and 12 during treatment with vitamin D(3 ) , 50,000 IU monthly . DESIGN , SETTING , AND PARTICIPANTS We conducted a r and omized double-blind , placebo-controlled multicenter trial of HIV-infected youth ages 18 - 24 yr , with viral load below 5000 copies/ml , on stable antiretroviral therapy . INTERVENTION INTERVENTION included vitamin D(3 ) , 50,000 IU ( n = 102 ) , or matching placebo ( n = 101 ) administered in three directly observed oral doses at monthly intervals . RESULTS At baseline , mean ( sd ) age was 20.9 ( 2.0 ) yr ; 37 % were female and 52 % African-American , and 54 % were vitamin D deficient/insufficient ( 25-OHD < 20 ng/ml ) , with no r and omized group differences . Of evaluable participants vitamin D deficient/insufficient at baseline who were administered vitamin D , 43 of 46 ( 93 % ) had sufficient 25-OHD by wk 12 . Vitamin D supplementation increased 25-OHD serum concentration from a baseline of 21.9 ( 13.3 ) to 35.9 ( 19.1 ) ng/ml at wk 12 ( P < 0.001 ) with no change for placebo . Although use of the antiretroviral efavirenz was associated with lower baseline 25-OHD concentration , efavirenz did not diminish the response to vitamin D supplementation . There was no treatment-related toxicity . CONCLUSIONS Supplementation with vitamin D(3 ) 50,000 IU monthly for three doses was safe . Increases in 25-OHD occurred in treated participants regardless of antiretroviral regimen BACKGROUND The optimal public health strategy for maintaining 25-hydroxyvitamin D [ 25(OH)D ] concentrations in schoolchildren in Mongolia is unknown . OBJECTIVE The objective was to compare the effectiveness of different supplement and fortified milk regimens to increase 25(OH)D concentrations in Mongolian schoolchildren . DESIGN Twenty-one classrooms of 579 children aged 9 - 11 y were r and omized to interventions with an equivalent content of vitamin D(3 ) : 1 ) a one-time seasonal supplement of 13,700 IU , 2 ) 300 IU/d from supplements , 3 ) 300 IU/d from fortified ultra-high-temperature pasteurized milk from the United States , 4 ) 300 IU/d from fortified pasteurized Mongolian milk , or 5 ) unfortified pasteurized Mongolian milk ( control ) . RESULTS In January , the mean ( ±SD ) serum 25(OH)D concentration was 8 ± 4 ng/mL ( 20 ± 10 nmol/L ) , and 98 % of the children had a concentration < 20 ng/mL ( 50 nmol/L ) . In March , concentrations were 8 ± 4 ng/mL after unfortified milk , 20 ± 6 ng/mL after fortified Mongolian milk , 29 ± 10 ng/mL after fortified US milk , 21 ± 6 ng/mL after daily supplements , and 12 ± 4 ng/mL after seasonal supplements ( each greater than unfortified milk , P < 0.01 ) . Seasonal supplementation was less effective than was daily supplementation ( P < 0.0001 ) . Despite consuming daily supplements or fortified milk , 41 % of the children still had concentrations < 20 ng/mL ( 50 nmol/L ) . Children with lower baseline 25(OH)D concentrations experienced slightly larger 25(OH)D responses to intervention than did children with higher concentrations ( P = 0.002 ) . CONCLUSIONS In this population with extremely low vitamin D concentrations , delivery of 300 IU vitamin D/d via supplements or in fortified milk improved 25(OH)D concentrations but failed to raise concentrations uniformly to > 20 ng/mL ( 50 nmol/L ) . The daily low-dose intervention was superior to the seasonal larger-dose intervention . Higher doses may be needed to prevent deficiency in schoolchildren in Mongolia and at other northern latitudes . This trial is registered at clinical trials.gov as NCT00886379 Background : Low bone mineral density ( BMD ) is a significant comorbidity in HIV . However , studies evaluating vitamin D supplementation on bone health in this population are limited . This study investigates changes in bone health parameters after 12 months of supplementation in HIV-infected youth with vitamin D insufficiency . Methods : This is a r and omized , active-control , double-blind trial investigating changes in bone parameters with 3 different vitamin D3 doses [ 18,000 ( st and ard/control dose ) , 60,000 ( moderate dose ) , and 120,000 IU/monthly ( high dose ) ] in HIV-infected youth 8–25 years old with baseline serum 25-hydroxyvitamin D ( 25(OH)D ) concentrations < 30 ng/mL.  BMD and bone turnover markers were measured at baseline and 12 months . Results : One hundred two subjects enrolled . Over 12 months , serum 25(OH)D concentrations increased with all doses , but the high dose ( ie , 120,000 IU/monthly ) maintained serum 25(OH)D concentrations in an optimal range ( ≥30 or ≥20 ng/mL ) throughout the study period for more subjects ( 85 % and 93 % , respectively ) compared with either the moderate ( 54 % and 88 % , respectively ) or st and ard dose ( 63 % and 80 % , respectively ) . All dosing groups showed some improvement in BMD ; however , only the high-dose arm showed significant decreases in bone turnover markers for both procollagen type 1 aminoterminal propeptide ( −3.7 ng/mL ; P = 0.001 ) and & Bgr;-CrossLaps ( −0.13 ng/mL ; P = 0.0005 ) . Conclusions : High-dose vitamin D supplementation ( 120,000 IU/mo ) given over 12 months decreases bone turnover markers in HIV-infected youth with vitamin D insufficiency , which may represent an early , beneficial effect on bone health . High vitamin D doses are needed to maintain optimal serum 25(OH)D concentrations To determine whether amounts of vitamin D lower than recommended doses are effective in preventing rickets , 256 term infants from two northern and two southern cities in China were studied in a r and omized trial of vitamin D supplementation ( 100 , 200 , or 400 IU/day ) during the first 6 months of life . Cord blood and 6-month blood sample s were collected and radiographs were obtained at 3 to 5 days and at 6 months of age . Cord serum 25-hydroxyvitamin D concentrations were lower in the north than in the south ( 5 vs 14 ng/ml ( 12.5 vs 35.0 nmol/L ) ; p less than 0.01 ) . Wrist ossification centers were less likely to be present at birth in the northern children than in the southern children ( p = 0.009 ) and were more likely to be present in infants born in the fall who had higher cord serum concentrations of 25-hydroxyvitamin D ( p = 0.04 ) . Serum 25-hydroxyvitamin D concentrations were lower in northern children 6 months of age than in southern children ( p = 0.005 ) and were higher with an increasing supplemental dosage of vitamin D ( p less than 0.001 ) , particularly in infants in the north . None of the infants had rickets at 6 months of age . Because of the low serum 25-hydroxyvitamin D concentrations , especially among infants in the north , it may be prudent to supplement the diet with vitamin D at a dose of 400 IU/day Vitamin D functions are not limited to skeletal health benefits and may extend to preservation of insulin secretion and insulin sensitivity . This review summarizes the literature related to potential vitamin D influences on glucose homeostasis and insulin sensitivity . Cross-sectional data provide some evidence that circulating 25-hydroxyvitamin D ( 25(OH)D ) is inversely associated with insulin resistance , although direct measurements of insulin sensitivity are required for confirmation . Reported associations with insulin secretion , however , are contradictory . Available prospect i ve studies support a protective influence of high 25(OH)D concentrations on type 2 diabetes mellitus risk . There is a general lack of consistency in vitamin D intervention outcomes on insulin secretion and sensitivity , likely due to differences in subject population s , length of interventions , and forms of vitamin D supplementation . Vitamin D receptor gene polymorphisms and vitamin D interactions with the insulin like growth factor system may further influence glucose homeostasis . The ambiguity of optimal vitamin D dosing regimens and optimal therapeutic concentrations of serum 25(OH)D limit available intervention studies . Future studies , including cross-sectional and prospect i ve , should be performed in population s at high risk for both vitamin D deficiency and type 2 diabetes mellitus . Well- design ed , placebo-controlled , r and omized intervention studies are required to establish a true protective influence of  vitamin D on glucose homeostasis Laboratory studies suggest that vitamin D ( vitD )  enhances chemotherapy‐induced cell death . The objective of this study was to determine whether pretreatment vitD levels were associated with response to neoadjuvant chemotherapy ( NACT ) in women with breast cancer . Study patients ( n = 82 ) were enrolled on the I‐SPY TRIAL , had HER2‐negative tumors , and available pretreatment serum .  VitD levels  were measured via DiaSorin radioimmunoassay . The primary outcome was pathologic residual cancer burden ( RCB ; dichotomized 0/1 vs. 2/3 ) . Secondary outcomes included biomarkers of proliferation , differentiation , and apoptosis ( Ki67 , grade , Bcl2 , respectively ) and 3‐year relapse‐free survival ( RFS ) . Mean and median vitD values were 22.7 ng/mL ( SD 11.9 ) and 23.1 ng/mL , respectively ; 72 % of patients had levels deemed “ insufficient ” ( < 30 ng/mL ) by the Institute of Medicine ( IOM ) . VitD level was not associated with attaining RCB 0/1 after NACT ( univariate odds ratio [ OR ] , 1.01 ; 95 % CI , 0.96–1.05 ) even after adjustment for hormone receptor status ( HR ) , grade , Ki67 , or body mass index ( BMI ) . Lower vitD levels were associated with higher tumor Ki67 adjusting for race ( OR , 0.95 ; 95 % CI , 0.90–0.99 ) . VitD level was not associated with 3‐year RFS , either alone ( hazard ratio [ HzR ] , 0.98 ; 95 % CI , 0.95–1.02 ) or after adjustment for HR , grade , Ki‐67 , BMI , or response .  VitD insufficiency was common at the time of breast cancer diagnosis among women who were c and i date s for NACT and was associated with a more proliferative phenotype .  However , vitD levels had no impact on tumor response to NACT or short‐term prognosis BACKGROUND Different dosing protocol s have been used for vitamin D supplementation , but there has been a lack of comparative data among them . OBJECTIVE Our objective was to determine whether the same cumulative dose of vitamin D3 produces different effects if it is given daily , weekly , or monthly . DESIGN Women , age 81 + /- 8 yr ( + /- sd , n = 48 ) , who had undergone surgery to repair hip fracture were r and omized to vitamin D3-supplementation protocol s at 1,500 IU daily , or 10,500 IU once weekly , or 45,000 IU once every 28 d. The primary outcome measure was the serum 25-hydroxyvitamin D [ 25(OH)D ] concentration attained . RESULTS Initially , serum 25(OH)D concentrations for daily , weekly , and monthly groups were , respectively , 15.13 + /- 6.9 , 15.7 + /- 10.1 , and 16.2 + /- 10.1 ng/ml . By d 7 , these had increased significantly in all the groups ( P < 0.001 ) . On the first day after the monthly dose , both serum 25(OH)D and serum 1,25-dihydroxyvitamin D had increased significantly ( P < 0.012 each ) , whereas these did not change significantly on the day after daily or weekly doses . After 2 months , serum 25(OH)D with daily , weekly , and monthly dosing were , respectively , 33.2 + /- 8.5 , 29.2 + /- 8.9 , and 37.1 + /- 10.3 ng/ml ; there were no significant differences among these values . CONCLUSIONS Supplementation with vitamin D can be achieved equally well with daily , weekly , or monthly dosing frequencies . Therefore , the choice of dose frequency can be based on whichever approach will optimize an individual 's adherence with long-term vitamin D supplementation BACKGROUND We previously found a high prevalence of vitamin D deficiency and low medication regimen compliance in Arab and East Indian women residing in the United Arab Emirates ( UAE ) . The appropriate dosing regimen for improving vitamin D status in this population is not known . OBJECTIVE We aim ed to determine the efficacy of daily and monthly supplementation with vitamin D2 , the only high-dose calciferol available in the UAE , in lactating and nulliparous women . DESIGN Healthy lactating ( n = 90 ) and nulliparous ( n = 88 ) women were r and omly assigned to consume 2000 IU vitamin D2/d or 60,000 IU vitamin D2/mo for 3 mo . Serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations were measured by radioimmunoassay at baseline and every month . RESULTS Most women had vitamin D deficiency [ ie , 25(OH)D < 50 nmol/L ] at study entry . Mean + /- SD 25(OH)D concentrations at 3 mo were significantly higher than baseline in both lactating ( 39.8 + /- 12.4 and 25.2 + /- 10.7 nmol/L , respectively ) and nulliparous ( 40.4 + /- 23.4 and 19.3 + /- 12.2 nmol/L , respectively ) women ( P < 0.001 for both ) . In total , vitamin D supplementation was effective in achieving serum 25(OH)D concentrations of > or=50 nmol/L in 21 ( 30 % ) of 71 women at endpoint . CONCLUSIONS Oral vitamin D2 supplementation with 2000 IU/d or 60,000 IU/mo for 3 mo was safe , and it increased serum 25(OH)D concentrations significantly ; however , only a small proportion of the women studied achieved concentrations of > or=50 nmol/L. This suggests that , when sunlight exposure is limited , doses of vitamin D2 higher than those currently studied may be needed . Monthly dosing appears to be a safe and effective alternative to daily dosing Public health recommendations do not distinguish between vitamin D2 and vitamin D3 , yet disagreement exists on whether these two forms should be considered equivalent . The objective of the present study was to evaluate the effect of a daily physiological dose of vitamin D2 or vitamin D3 on 25-hydroxyvitamin D ( 25(OH)D ) status over the winter months in healthy adults living in Dunedin , New Zeal and ( latitude 46 ° S ) . Participants aged 18 - 50 years were r and omly assigned to 25 μg ( 1000 IU ) vitamin D3 ( n 32 ) , 25 μg ( 1000 IU ) vitamin D2 ( n 31 ) or placebo ( n 32 ) daily for 25 weeks beginning at the end of summer . A per- protocol approach , which included ≥ 90 % supplement compliance , was used for all analyses . Serum 25-hydroxyvitamin D3 ( 25(OH)D3 ) , 25-hydroxyvitamin D2 ( 25(OH)D2 ) and parathyroid hormone ( PTH ) were measured at baseline and at 4 , 8 , 13 and 25 weeks . Geometric mean total serum 25(OH)D concentrations ( sum of 25(OH)D2 and 25(OH)D3 ) at baseline was 80 nmol/l . After 25 weeks , participants r and omised to D2 and placebo had a significant reduction in serum 25(OH)D3 concentrations over the winter months compared with vitamin D3-supplemented participants ( both P < 0.001 ) . Supplementation with vitamin D2  increased serum 25(OH)D2 but produced a 9 ( 95 % CI 1 , 17 ) nmol/l greater decline in the 25(OH)D3 metabolite compared with placebo ( P < 0.036 ) . Overall , total serum 25(OH)D concentrations were 21 ( 95 % CI 14 , 30 ) nmol/l lower in participants receiving vitamin D2 compared with those receiving D3 ( P < 0.001 ) , among whom total serum 25(OH)D concentrations remained unchanged . No intervention-related changes in PTH were observed . Daily supplementation of vitamin D3 was more effective than D2 ; however , the functional consequence of the differing metabolic response warrants further investigation BACKGROUND Vitamin D supplementation is recommended for breastfed infants .  Maternal supplementation beginning in gestation is a potential alternative , but its efficacy in maintaining infant 25-hydroxyvitamin D [ 25(OH)D ] concentration after birth is unknown . OBJECTIVES We determined the effect of 3 doses of maternal vitamin D supplementation beginning in gestation and continued in lactation on infant serum 25(OH)D and compared the prevalence of infant serum 25(OH)D cutoffs ( > 30 , > 40 , > 50 , and > 75 nmol/L ) by dose at 8 wk of age . DESIGN Pregnant women ( n = 226 ) were r and omly allocated to receive 10 , 25 , or 50 μg vitamin D₃/d from 13 to 24 wk of gestation until 8 wk postpartum , with no infant supplementation . Mother and infant blood was collected at 8 wk postpartum . RESULTS At 8 wk postpartum , mean [ nmol/L ( 95 % CI ) ] infant 25(OH)D at 8 wk was higher in the 50-μg/d [ 75 ( 67 , 83 ) ] than in the 25-μg/d [ 52 ( 45 , 58 ) ] or 10-μg/d [ 45 ( 38 , 52 ) ] vitamin D groups ( P < 0.05 ) . Fewer infants born to mothers in the 50-μg/d group had a 25(OH)D concentration < 30 nmol/L ( indicative of deficiency ) than infants in the 25- and 10-μg/d groups , respectively ( 2 % compared with 16 % and 43 % ; P < 0.05 ) . Fewer than 15 % of infants in the 10- or 25-μg/d groups achieved a 25(OH)D concentration > 75 nmol/L compared with 44 % in the 50-μg/d group ( P < 0.05 ) . Almost all infants ( ∼98 % , n = 44 ) born to mothers in the 50-μg/d group achieved a 25(OH)D concentration > 30 nmol/L. At 8 wk postpartum , mean maternal 25(OH)D concentration was higher in the 50-μg/d [ 88 ( 84 , 91 ) ] than in the 25-μg/d [ 78 ( 74 , 81 ) ] or 10-μg/d [ 69 ( 66 , 73 ) ] groups ( P < 0.05 ) . CONCLUSIONS Maternal supplementation beginning in gestation with 50 μg vitamin D₃/d protects 98 % of unsupplemented breastfed infants against 25(OH)D deficiency ( < 30 nmol/L ) to at least 8 wk , whereas 10 or 25 μg vitamin D/d protects only 57 % and 84 % of infants , respectively Background : There are conflicting views in the literature as to whether vitamin D2 and vitamin D3 are equally effective in increasing and maintaining serum concentrations of 25-hydroxyvitamin D [ 25(OH)D ] , particularly at lower doses of vitamin D. Objective : We aim ed to investigate whether vitamin D2 or vitamin D3 fortified in juice or food , at a relatively low dose of 15 μg/d , was effective in increasing serum total 25(OH)D and to compare their respective efficacy in South Asian and white European women over the winter months within the setting of a large r and omized controlled trial . Design : A r and omized , double-blind , placebo-controlled food-fortification trial was conducted in healthy South Asian and white European women aged 20 - 64 y ( n = 335 ; Surrey , United Kingdom ) who consumed placebo , juice supplemented with 15 μg vitamin D2 , biscuit supplemented with 15 μg vitamin D2 , juice supplemented with 15 μg vitamin D3 , or biscuit supplemented with 15 μg vitamin D3 daily for 12 wk  . Serum 25(OH)D was measured by liquid chromatography-t and em mass spectrometry at baseline and at weeks 6 and 12 of the study . Results : Postintervention in the 2 ethnic groups combined , both the vitamin D3 biscuit and the vitamin D3 juice groups showed a significantly greater absolute incremental change ( Δ ) in total 25(OH)D when compared with the vitamin D2 biscuit group [ Δ ( 95 % CI ) : 15.3 nmol/L ( 7.4 , 23.3 nmol/L ) ( P < 0.0003 ) and 16.0 nmol/L ( 8.0 , 23.9 nmol/L ) ( P < 0.0001 ) ] , the vitamin D2 juice group [ Δ ( 95 % CI ) : 16.3 nmol/L ( 8.4 , 24.2 nmol/L ) ( P < 0.0001 ) and 16.9 nmol/L ( 9.0 , 24.8 nmol/L ) ( P < 0.0001 ) ] , and the placebo group [ Δ ( 95 % CI ) : 42.3 nmol/L ( 34.4 , 50.2 nmol/L ) ( P < 0.0001 ) and 42.9 nmol/L ( 35.0 , 50.8 nmol/L ) ( P < 0.0002 ) ] . Conclusions : With the use of a daily dose of vitamin D relevant to public health recommendations ( 15 μg ) and in vehicles relevant to food-fortification strategies , vitamin D3 was more effective than vitamin D2 in increasing serum 25(OH)D in the wintertime . Vitamin D3 may therefore be a preferential form to optimize vitamin D status within the general population . This trial was registered at www.controlled-trials.com as IS RCT N23421591 Background Declining serum concentrations of 25-hydroxyvitamin D seen in the fall and winter as distance increases from the equator may be a factor in the seasonal increased prevalence of influenza and other viral infections . This study was done to determine if serum 25-hydroxyvitamin D concentrations correlated with the incidence of acute viral respiratory tract infections . Methodology / Findings In this prospect i ve cohort study serial monthly concentrations of 25-hydroxyvitamin D were measured over the fall and winter 2009–2010 in 198 healthy adults , blinded to the nature of the substance being measured . The participants were evaluated for the development of any acute respiratory tract infections by investigators blinded to the 25-hydroxyvitamin D concentrations . The incidence of infection in participants with different concentrations of vitamin D was determined . One hundred ninety-five ( 98.5 % ) of the enrolled participants completed the study . Light skin pigmentation , lean body mass , and supplementation with vitamin D were found to correlate with higher concentrations of 25-hydroxyvitamin D. Concentrations of 38 ng/ml or more were associated with a significant ( p<0.0001 ) two-fold reduction in the risk of developing acute respiratory tract infections and with a marked reduction in the percentages of days ill . Conclusions / Significance Maintenance of a 25-hydroxyvitamin D serum concentration of 38 ng/ml or higher should significantly reduce the incidence of acute viral respiratory tract infections and the burden of illness caused thereby , at least during the fall and winter in temperate zones . The findings of the present study provide direction for and call for future interventional studies examining the efficacy of vitamin D supplementation in reducing the incidence and severity of specific viral infections , including influenza , in the general population and in sub population s with lower 25-hydroxyvitamin D concentrations , such as pregnant women , dark skinned individuals , and the obese BACKGROUND Persons with limited exposure to ultraviolet B light , including space travelers , may not receive enough vitamin D. Recent studies indicate that optimal serum 25-hydroxyvitamin D [ 25(OH)D ] should be > or = 80 nmol/L. OBJECTIVE This study was design ed to evaluate the effectiveness of 3 doses of vitamin D to raise and maintain 25(OH)D to a concentration > 80 nmol/L in persons with limited ultraviolet B light exposure . DESIGN This was a 5-mo , prospect i ve , r and omized , double-blind study of vitamin D supplementation . It was conducted during winter in Anta rct ica at the McMurdo Station , when ultraviolet B radiation levels are essentially zero . The 55 subjects were r and omly divided into 3 groups for vitamin D supplementation : 2000 IU/d ( n = 18 ) , 1000 IU/d ( n = 19 ) , and 400 IU/d ( n = 18 ) . An additional 7 subjects did not take supplements or took supplements of their own choosing . Blood sample s were collected about every 2 mo during the winter . RESULTS About 5 mo after supplementation started , 25(OH)D increased to 71 + /- 23 nmol/L in the 2000-IU/d group , 63 + /- 25 nmol/L in the 1000-IU/d group , and 57 + /- 15 nmol/L in the 400-IU/d group and decreased to 34 + /- 12 nmol/L in the group not taking supplements . CONCLUSIONS These data will enable us to provide space crews with evidence -based recommendations for vitamin D supplementation . The findings also have implication s for other persons with limited ultraviolet light exposure , including polar workers and the elderly Eighteen term , healthy , appropriate for gestational age , breast-fed infants were studied in a double-blind prospect i ve study to determine whether or not supplemental vitamin D affected bone mineralization .  All patients were from a single , private pediatric practice . Nine infants were r and omly assigned to a vitamin D supplement of 400 IU/day and nine infants to a placebo . By 12 weeks of age , infants receiving placebo had a significant decrease in bone mineralization and in serum 25-hydroxyvitamin D concentrations compared to the vitamin D-supplemented group . It is not known whether or not the increased BMC at 12 weeks of age in vitamin D-supplemented breast-fed infants is of ultimate value . Supplemental vitamin D may be necessary for optimal bone mineralization in term breast-fed infants . A longer follow-up study and additional analyses are required to make conclusive statements Objective : Our study aim ed to investigate the nutritional vitamin D status of school children aged 9–15 years and white-collar workers in Zhejiang province , and evaluate the efficacy of low-dose-oral vitamin D supplementation in both population s. Methods : We conducted a prospect i ve controlled trial during March 2014 to November 2015 , comparing the efficacy of vitamin D supplements ( 400 IU/day ) with non-intervention for 18 months in school children aged 9–15 years . Meanwhile , a before-after study was conducted among white-collar workers for 1 year . Serum 25(OH)D concentration was measured at baseline and after vitamin D supplementation , respectively . Results : At the baseline , 95 % of school children and 84 % of adult participants had vitamin D deficiency ( < 20 ng/mL ) . In school children , no difference was observed between the intervention and control groups with regard to anthropometric data . Serum 25(OH)D concentrations of the school children intervention group , school children control group and white-collar workers were 12.77 ± 3.01 ng/mL , 14.17 ± 3.59 ng/mL and 16.58 ± 3.66 ng/mL at baseline and increased to 17.34 ± 3.78 ng/mL , 18.04 ± 4.01 ng/mL and 17.75 ± 5.36 ng/mL after vitamin D supplementation , respectively . Although , after adjusting for potential confounders , the 400 IU oral vitamin D supplementation increased serum 25(OH)D concentration in school children ( β = 0.81 , p = 0.0426 ) as well as in white-collar workers ( p = 0.0839 ) , the prevalence of vitamin D deficiency was still very high among school children ( 79.23 % in intervention group and 72.38 % in control group ) and white-collar workers ( 76.00 % ) . Conclusions : High prevalence of vitamin D deficiency was common in these two study population s. Daily doses of 400 IU oral vitamin D supplementation was not able to adequately increase serum 25(OH)D concentrations . A suitable recommendation regarding the level of vitamin D supplementation is required for this Chinese population Summary Whether infant vitamin D supplementation may have long-term bone benefits is unclear . In this study , breastfed infants who received vitamin dosages greater than 400 IU/day did not have higher bone mineralization at 3 years . This study provides important data to inform pediatric public health recommendations for vitamin D. Introduction North American health agencies recommend breastfed infants should be supplemented with 400 IU of vitamin D/day to support bone health . Few studies examined the long-term benefits of early life vitamin D supplementation on bone mineralization . The objective of this study was to determine if a dose-response relationship exists between infant vitamin D supplementation , vitamin D status , and bone outcomes at 3 years of age . Methods This was a double-blind r and omized trial of 132 , 1-month-old healthy , breastfed infants from Montréal , Canada , between 2007 and 2010 . In this longitudinal analysis , 87 infants ( 66 % ) returned for follow-up at 3 years of age , between 2010 and 2013 . At 1 month of age , participants were r and omly assigned to receive oral cholecalciferol ( vitamin D3 ) supplements of 400 , 800 , 1200 , or 1600 IU/day until 12 months of age . Lumbar spine vertebrae 1–4 ( LS ) bone mineral density ( BMD ) , LS and whole body bone mineral content ( BMC ) , and mineral accretion were measured by dual-energy x-ray absorptiometry at 3 years . Results At follow-up , the treatment groups were similar in terms of diet , sun exposure , and demographics . There were no significant differences among the groups in LS or whole body BMC , BMD , or accretion . Although , 25(OH)D concentrations were not different among the groups , higher doses ( 1200 and 1600 IU/day ) achieved higher 25(OH)D area under the curve from 1 to 36 months vs. 400 IU/day . Conclusions This is the first longitudinal follow-up of an infant vitamin D dose-response study which examines bone mineralization at 3 years of age . Dosages higher than 400 IU/day do not appear to provide additional benefits to the bone at follow-up . Larger studies with more ethnically diverse groups are needed to confirm these results Background : Vitamin D insufficiency poses a problem in many parts of the world , the elderly being an especially vulnerable group . This insufficiency results from an inadequate amount of sunshine and a low dietary intake of vitamin D. Typically , insufficiency is accompanied with high intact parathyroid hormone , ( S-iPTH ) concentrations . Aims of the Study : We studied how serum 25-hydroxy vitamin D ( S-25-OHD ) concentrations respond to different doses of vitamin D3 supplementation . Secondly to determine the smallest efficient dose to maintain serum 25-OHD concentration above the insufficiency level . We also studied which dose would be efficient in decreasing S-iPTH concentration in these subjects . Subjects and Methods : Forty-nine 65- to 85-year-old women participated . The women were r and omly assigned into one of four groups receiving 0 ( placebo ) , 5 , 10 or 20 μg of vitamin D3 daily for 12 weeks . Fasting morning blood was drawn at the beginning of the study , and thereafter every second week . Calciotropic variables were assessed from serum and urine sample s. Results : The S-25-OHD concentration increased significantly ( p < 0.001 ) in all supplemented groups [ 5 μg : by 10.9 ( 8.5 ) nmol/L , 10 μg : by 14.4 ( 6.9 ) nmol/L , 20 μg : by 23.7 ( 11.9 ) nmol/L ] , whereas it decreased in the placebo group by 8.3 ( 13.2 ) nmol/L. Equilibrium in S-25-OHD concentration was reached in all groups after 6 weeks of supplementation at 57.7 ( 8.9 ) nmol/L , 59.9 ( 8.9 ) nmol/L and 70.9 ( 8.9 ) nmol/L in the groups with increasing vitamin D supplementation . The dose-response to supplementation decreased with increasing vitamin D status at baseline , r = −0.513 , p = 0.002 . S-iPTH tended to decrease in those with highest dose response to supplementation . Conclusions : A clear dose response was noted in S-25-OHD to different doses of vitamin D3 . The recommended dietary intake of 15 μg is adequate to maintain the S-25-OHD concentration around 40–55 nmol/L during winter , but if the optimal S-25-OHD is higher than that even higher vitamin D intakes are needed . Interestingly , subjects with lower vitamin D status at baseline responded more efficiently to supplementation than those with more adequate status Low serum 25-hydroxyvitamin D ( 25(OH)D ) has been shown to correlate with increased risk of type 2 diabetes . Small , observational studies suggest an action for vitamin D in improving insulin sensitivity and /or insulin secretion . The objective of the present study was to investigate the effect of improved vitamin D status on insulin resistance ( IR ) , utilising r and omised , controlled , double-blind intervention administering 100 microg ( 4000 IU ) vitamin D(3 ) ( n 42 ) or placebo ( n 39 ) daily for 6 months to South Asian women , aged 23 - 68 years , living in Auckl and , New Zeal and . Subjects were insulin resistant - homeostasis model assessment 1 (HOMA1)>1.93 and had serum 25(OH)D concentration < 50 nmol/l . Exclusion criteria included diabetes medication and vitamin D supplementation > 25 microg ( 1000 IU)/d . The HOMA2 computer model was used to calculate outcomes . Median ( 25th , 75th percentiles ) serum 25(OH)D(3 ) increased significantly from 21 ( 11 , 40 ) to 75 ( 55 , 84 ) nmol/l with supplementation . Significant improvements were seen in insulin sensitivity and IR ( P = 0.003 and 0.02 , respectively ) , and fasting insulin decreased ( P = 0.02 ) with supplementation compared with placebo . There was no change in C-peptide with supplementation . IR was most improved when endpoint serum 25(OH)D reached > or = 80 nmol/l . Secondary outcome variables ( lipid profile and high sensitivity C-reactive protein ) were not affected by supplementation . In conclusion , improving vitamin D status in insulin resistant women result ed in improved IR and sensitivity , but no change in insulin secretion . Optimal vitamin D concentrations for reducing IR were shown to be 80 - 119 nmol/l , providing further evidence for an increase in the recommended adequate levels . Registered Trial No. ACTRN12607000642482 BACKGROUND Association studies have suggested that lower circulating 25-hydroxyvitamin D [ 25(OH)D ] in African Americans may partially underlie higher rates of cardiovascular disease and cancer in this population . Nonetheless , the relation between vitamin D supplementation and 25(OH)D concentrations in African Americans remains undefined . OBJECTIVE Our primary objective was to determine the dose-response relation between vitamin D and plasma 25(OH)D. DESIGN A total of 328 African Americans in Boston , MA , were enrolled over 3 winters from 2007 to 2010 and r and omly assigned to receive a placebo or 1000 , 2000 , or 4000 IU vitamin D₃/d for 3 mo . Subjects completed sociodemographic and dietary question naires , and plasma sample s were drawn at baseline and 3 and 6 mo . RESULTS Median plasma 25(OH)D concentrations at baseline were 15.1 , 16.2 , 13.9 , and 15.7 ng/mL for subjects r and omly assigned to receive the placebo or 1000 , 2000 , or 4000 IU/d , respectively ( P = 0.63 ) . The median plasma 25(OH)D concentration at 3 mo differed significantly between supplementation arms at 13.7 , 29.7 , 34.8 , and 45.9 ng/mL , respectively ( P < 0.001 ) . An estimated 1640 IU vitamin D₃/d was needed to raise the plasma 25(OH)D concentration to ≥ 20 ng/mL in ≥ 97.5 % of participants , whereas a dose of 4000 IU/d was needed to achieve concentrations ≥ 33 ng/mL in ≥ 80 % of subjects . No significant hypercalcemia was seen in a subset of participants . CONCLUSIONS Within African Americans , an estimated 1640 IU vitamin D₃/d was required to achieve concentrations of plasma 25(OH)D recommended by the Institute of Medicine , whereas 4000 IU/d was needed to reach concentrations predicted to reduce cancer and cardiovascular disease risk in prospect i ve observational studies . These results may be helpful for informing future trials of disease prevention Summary Daily dosing with vitamin D often fails to achieve optimal outcomes , and it is uncertain what the target level of 25-hydroxyvitamin D should be . This study found that large loading doses of vitamin D3 rapidly and safely normalize 25OHD levels , and that monthly dosing is similarly effective after 3–5 months . With baseline 25OHD > 50 nmol/L , vitamin D supplementation does not reduce PTH levels . Introduction There is concern that vitamin D supplementation doses are frequently inadequate , and that compliance with daily medication is likely to be suboptimal . Methods This r and omized double-blind trial compares responses to three high-dose vitamin D3 regimens and estimates optimal 25-hydroxyvitamin D ( 25OHD ) levels , from changes in parathyroid hormone ( PTH ) , and procollagen type I amino-terminal propeptide ( P1NP ) in relation to baseline 25OHD . Sixty-three elderly participants were r and omized to three regimens of vitamin D supplementation : a 500,000-IU loading dose ; the loading dose plus 50,000 IU/month ; or 50,000 IU/month . Results The Loading and Loading + Monthly groups showed increases in 25OHD of 58 ± 28 nmol/L from baseline to 1 month . Thereafter , levels gradually declined to plateaus of 69 ± 5 nmol/L and 91 ± 4 nmol/l , respectively . In the Monthly group , 25OHD reached a plateau of ~80 ± 20 nmol/L at 3–5 months . There were no changes in serum calcium concentrations . PTH and P1NP were only suppressed by vitamin D treatment in those with baseline 25OHD levels < 50 and < 30 nmol/L , respectively . Conclusions Large loading doses of vitamin D3 rapidly and safely normalize 25OHD levels in the frail elderly . Monthly dosing is similarly effective and safe , but takes 3–5 months for plateau 25OHD levels to be reached OBJECTIVES During half of the year , cutaneous synthesis of 25-hydroxyvitamin D ( 25(OH)D ) is not detectable at northern latitudes , leaving the population dependent on other sources for optimal vitamin D status . During April to September , 25(OH)D status may be improved by solar exposure . In this study , we measured seasonal differences in serum 25(OH)D concentrations and identified the major predictors of summer 25(OH)D concentrations . DESIGN We assessed  serum 25(OH)D concentrations during both winter and summer amongst 100 women , aged 61 - 83 years , r and omly sample d from the Swedish Mammography Cohort . Participants completed two detailed question naires covering diet , use of dietary supplements and sun-related behaviour , the first in January through March and a second time in August through September . RESULTS The mean seasonal increase in serum 25(OH)D concentrations was 38 % from mean 72 + /- 23 nmol L(-1 ) during winter to 99 + /- 29 nmol L(-1 ) in summer . High summer 25(OH)D concentrations were associated with higher winter concentrations , preference of staying in sun instead of shade , having a nonsensitive skin type and normal body mass index . Based on multiple linear regression modelling , preferring sun , having nonsensitive skin type and normal weight as compared with preferring shade , having sensitive skin type and being obese , was associated with a 64 nmol L(-1 ) higher 25(OH)D concentrations during summer . CONCLUSIONS Women with high winter 25(OH)D serum concentrations  , with preference of staying in the sun instead of shade during summer , a skin type allowing for longer sun exposure and a normal weight had the highest summer 25(OH)D concentrations Summary On September 29 , 2011 , acknowledged experts in the field of vitamin D , mainly European , were brought together in order to discuss the recent scientific advances in relation to vitamin D : the current requirements and associations with various health outcomes . In this article , the discussion s result ing from the meeting are summarized . Introduction Several groups at risk for developing vitamin D insufficiency have been identified . Accordingly , review s indicate that a significant percentage of the population worldwide have serum 25-hydroxyvitamin D levels below 50 nmol/l . In addition to the role of vitamin D in bone health , recent studies suggest that it may play a pivotal role in other systems , e.g. , the cardiovascular system , pancreas , muscle , immune system and brain . Most evidence , however , is obtained from observational studies and yet inconclusive . Methods To exchange and broaden knowledge on the requirements for vitamin D and its effect on various health outcomes , a workshop entitled “ Vitamin D Expert Meeting : Do we get enough ? ” , was organized . Results Despite low vitamin D levels worldwide , consensus on the definition of deficiency is not yet reached . In order to define cut-off points for vitamin D whilst taking into account extraskeletal health effects , r and omized controlled trials in these fields are warranted . The experts do emphasize that there is evidence to suggest an important role for vitamin D in the maintenance of optimal bone health at all ages and that vitamin D supplementation , in most studies co-administered with calcium , reduces fracture risk in the senior population . Conclusion To reach a serum 25-hydroxyvitamin D level of 50 nmol/l older adults aged ≥65 years are therefore recommended to meet a mean daily vitamin D intake of 20 μg ( 800 IU ) , which is best achieved with a supplement Although geographic ecological studies and observational studies find that ultraviolet B exposure and 25-hydroxyvitamin D [ 25(OH)D ] concentrations are inversely correlated with 15–20 types of cancer , few r and omized controlled trials ( RCTs ) of vitamin D support those findings . The poor design of some RCTs may account for that lack of support . Most vitamin D RCTs to date have considered the vitamin D dose , rather than initial , final , or changes in , serum 25(OH)D concentrations . Here a model is developed for use in design ing and analyzing vitamin D RCTs with application to cancer incidence . The input variables of the model are  vitamin D dose , baseline and achieved 25(OH)D concentrations , known rates of cancer for the population  , and numbers of participants for the treatment and placebo arms is estimated — vitamin D dosage and numbers of participants are varied to achieve desired hazard ratio significance , using information from two  vitamin D RCTs on cancer incidence conducted in Nebraska with good agreement between the model estimates and reported hazard ratios . Further improvements to the conduct of vitamin D RCTs would be to start the trial with a moderate bolus dose to achieve the desired 25(OH)D concentrations , and bloodspot 25(OH)D assay use in summer and winter annually to monitor seasonal and long-term changes in 25(OH)D concentration and compliance , and to allow dosage adjustment for achievement of desired vitamin D status Severe vitamin D deficiency in mothers and their breastfed infants is a significant health problem in the Middle East . Supplementation of the breastfed infant alone with the recommended dose of vitamin D may be insufficient in high-risk population . We investigated the effect of combined maternal and infant vitamin D supplementation on vitamin D status of the breastfed infant . We examined also the effect of supplementation on vitamin D antirachitic activity of breast milk in a subset of mothers . Healthy breastfeeding mothers ( n = 90 ) were r and omly assigned to 2000 IU daily ( group 1 ) or 60,000 IU monthly ( group 2 ) of vitamin D(2 ) , and all their infants ( n = 92 ) received 400 IU daily of vitamin D(2 ) for 3 months . Most infants had vitamin D deficiency - 25-hydroxyvitamin D [ 25(OH)D ] < or= 37.5 nmol L(-1)- at study entry .  Serum 25(OH)D concentrations at 3 months increased significantly from baseline in infants of mothers in group 1 ( 13.9 + /- 8.6 vs. 49.6 + /- 18.5 nmol L(-1 ) , P < 0.0001 ) and group 2 ( 13.7 + /- 12.1 vs. 44.6 + /- 15.0 nmol L(-1 ) , P < 0.0001 ) . Maternal and infant serum 25(OH)D concentrations correlated positively at baseline ( r = 0.36 , P = 0.01 ) and 3 months ( r = 0.46 , P = 0.002 ) . Milk antirachitic activity increased from undetectable ( < 20 IU L(-1 ) ) to a median of 50.9 IU L(-1 ) . In conclusion , combined maternal and infant vitamin D supplementation was associated with a threefold increase in infants ' serum 25(OH)D concentrations and a 64 % reduction in the prevalence of vitamin D deficiency without causing hypervitaminosis Severe vitamin D deficiency is common among Muslim immigrants . The dose necessary to correct the deficiency and its consequence for bone health are not known for immigrants . The aim was to assess the effect of relatively low dosages of supplemental vitamin D on vitamin D and bone status in Pakistani immigrants . This 1-year-long r and omised double-blinded placebo-controlled intervention with vitamin D3 ( 10 and 20 microg/d ) included girls ( 10.1 - 14.7 years ) , women ( 18.1 - 52.7 years ) and men ( 17.9 - 63.5 years ) of Pakistani origin living in Denmark . The main endpoints were serum 25-hydroxyvitamin D ( S-25OHD ) , parathyroid hormone , bone turnover markers and bone mass . The study showed that supplementation with 10 and 20 microg vitamin D3 per d increased S-25OHD concentrations similarly in vitamin D-deficient Pakistani women ( 4-fold ) , and that 10 microg increased S-25OHD concentrations 2-fold and 20 microg 3-fold in Pakistani men . S-25OHD concentrations increased at 6 months and were stable thereafter . Baseline S-25OHD concentrations tended to be lower in girls and women than in men ; females achieved about 46 nmol/l and men 55 nmol/l after supplementation . Serum intact parathyroid hormone concentrations decreased at 6 months , but there was no significant effect of the intervention on bone turnover markers and dual-energy X-ray absorptiometry measurements of the whole body and lumbar spine BACKGROUND Knowledge gaps have contributed to considerable variation among international dietary recommendations for vitamin D. OBJECTIVE We aim ed to establish the distribution of dietary vitamin D required to maintain serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations above several proposed cutoffs ( ie , 25 , 37.5 , 50 , and 80 nmol/L ) during wintertime after adjustment for the effect of summer sunshine exposure and diet . DESIGN A r and omized , placebo-controlled , double-blind 22-wk intervention study was conducted in men and women aged 20 - 40 y ( n = 238 ) by using different supplemental doses ( 0 , 5 , 10 , and 15 microg/d ) of vitamin D(3 ) throughout the winter .  Serum 25(OH)D concentrations were measured by using enzyme-linked immunoassay at baseline ( October 2006 ) and endpoint ( March 2007 ) . RESULTS There were clear dose-related increments ( P < 0.0001 ) in serum 25(OH)D with increasing supplemental vitamin D(3 ) . The slope of the relation between  vitamin D intake and serum 25(OH)D was 1.96 nmol x L(-1 ) x microg(-1 ) intake . The vitamin D intake that maintained serum 25(OH)D concentrations of > 25 nmol/L in 97.5 % of the sample was 8.7 microg/d . This intake ranged from 7.2 microg/d in those who enjoyed sunshine exposure , 8.8 microg/d in those who sometimes had sun exposure , and 12.3 microg/d in those who avoided sunshine . Vitamin D intakes required to maintain serum 25(OH)D concentrations of > 37.5 , > 50 , and > 80 nmol/L in 97.5 % of the sample were 19.9 , 28.0 , and 41.1 microg/d , respectively . CONCLUSION The range of vitamin D intakes required to ensure maintenance of wintertime vitamin D status [ as defined by incremental cutoffs of serum 25(OH)D ] in the vast majority ( > 97.5 % ) of 20 - 40-y-old adults , considering a variety of sun exposure preferences , is between 7.2 and 41.1 microg/d To evaluate the effect of maternal dietary vitamin D intake on infant vitamin D status in a country with a temperate climate , but where the commercial milk supply is not vitamin D fortified , this r and omized , double-blind study was conducted on term mother-infant pairs during the winter months . Well-nourished , white nursing mothers were given a placebo , 500 IU vitamin D/day or 1,000 IU vitamin D/day ; their infants were not given supplemental vitamin D. After six weeks , mothers receiving supplemental vitamin D had higher levels of 25-hydroxyvitamin D than had mothers receiving placebo . A direct relationship was observed between maternal and infant levels of 25-hydroxyvitamin D at six weeks , implying that maternal vitamin D intake directly affects the vitamin D concentration in breast milk . A control group of infants who had received 400 IU vitamin D/day had even higher concentrations of 25-hydroxyvitamin D , suggesting that infant supplementation with vitamin D is more efficacious than maternal supplementation . Despite the favorable climate in South Africa , during winter breast-fed infants have low serum vitamin D values if maternal dietary vitamin D intake is low OBJECTIVE To determine whether a single monthly supplement is as effective as a daily maternal supplement in increasing breast milk vitamin D to achieve vitamin D sufficiency in their infants . PATIENTS AND METHODS Forty mothers with exclusively breast-fed infants were r and omized to receive oral cholecalciferol ( vitamin D3 ) 5000 IU/d for 28 days or 150,000 IU once . Maternal serum , breast milk , and urine were collected on days 0 , 1 , 3 , 7 , 14 , and 28 ; infant serum was obtained on days 0 and 28 . Enrollment occurred between January 7 , 2011 , and July 29 , 2011 . RESULTS In mothers given daily cholecalciferol , concentrations of serum and breast milk cholecalciferol attained steady levels of 18 and 8 ng/mL , respectively , from day 3 through 28 . In mothers given the single dose , serum and breast milk cholecalciferol peaked at 160 and 40 ng/mL , respectively , at day 1 before rapidly declining . Maternal milk and serum cholecalciferol concentrations were related ( r=0.87 ) . Infant mean serum 25-hydroxyvitamin D concentration increased from 17±13 to 39±6 ng/mL in the single-dose group and from 16±12 to 39±12 ng/mL in the daily-dose group ( P=.88 ) . All infants achieved serum 25-hydroxyvitamin D concentrations of more than 20 ng/mL. CONCLUSION Either single-dose or daily-dose cholecalciferol supplementation of mothers provided breast milk concentrations that result in vitamin D sufficiency in breast-fed infants . CLINICAL TRIAL REGISTRATION clinical trials.gov NCT01240265 Serum 25-hydroxyvitamin D [ 25(OH)D ] , calcium , phosphorus , and alkaline phosphatase activities were measured from birth to 6 - 9 mo of age in 60 healthy neonates to assess the effectiveness and potential toxicity of three intermittent oral doses of cholecalciferol . Two weeks after a first dose of 15 , 5 , or 2.5 mg , 25(OH)D concentrations reached 307 + /- 160 , 150 + /- 55 , and 92 + /- 42 nmol/L , respectively . Prolonged vitamin D overload , up to 6 mo , was found in 50 % of the children given 15 mg , but not in the other infants . Serum calcium transiently increased 2 wk after 15 mg but not after the lower doses . Oral doses of 2.5 mg given every 3 mo appear to provide the best protection against vitamin D deficiency and vitamin D overload in high-risk infant population s that are unsuitable for daily vitamin D supplementation OBJECTIVE . Vitamin D insufficiency occurs commonly in HIV-infected youth in the United States . In light of the importance of vitamin D for skeletal and nonskeletal health , including innate immunity , developing methods for improving vitamin D status in HIV-infected children and adolescents is an important area of clinical research . The objective of this study was to evaluate the effect of administration of oral cholecalciferol , 100000 IU every 2 months , and 1 g/day calcium on serum 25-hydroxyvitamin D concentrations , serum and urine calcium , and HIV disease progression during a 12-month period . METHODS . HIV-infected children and adolescents who were aged 6 to 16 years were r and omly assigned to receive vitamin D ( 100000 IU bimonthly ) and calcium ( 1 g/day ; n = 29 ) or double placebo ( n = 27 ) . Serum 25-hydroxyvitamin D concentrations as measured by radioimmunoassay , albumin-corrected calcium concentrations , and spot urinary calcium-creatinine ratios were determined monthly . RESULTS . No abnormalities in serum calcium concentration were observed . One participant who received placebo  developed hypercalciuria . No group differences were seen in the change in CD4 count or CD4 % or viral load during 12 months . The overall mean monthly serum 25-hydroxyvitamin D concentrations were higher in the group that received vitamin D and calcium than in the placebo group , as was the monthly serum 25-hydroxyvitamin D area under the curve . After completing 12 months of study , 2 ( 6.7 % ) participants in the group that received vitamin D and calcium had a trough serum 25-hydroxyvitamin D concentration < 20 ng/mL compared with 14 ( 50 % ) in the placebo group . Twelve ( 44.4 % ) in the group that received vitamin D and calcium  had a trough serum 25-hydroxyvitamin D concentration of ≥30 ng/mL compared with 3 ( 11.1 % ) in the placebo group . CONCLUSIONS . Administration of oral cholecalciferol to HIV-infected children and adolescents at a dosage of 100000 IU every 2 months , together with 1 g/day calcium , is safe and results in significant increases in serum 25-hydroxyvitamin D concentrations BACKGROUND Knowledge gaps have contributed to considerable variation ( between 0 and 15 μg/d ) in international dietary recommendations for  vitamin D in adolescents . OBJECTIVE We aim ed to establish the distribution of dietary vitamin D required to maintain serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations above several proposed cutoffs ( 25 , 37.5 , 40 , and 50 nmol/L ) during wintertime in adolescent white girls . DESIGN Data ( baseline and 6 mo ) from 2 r and omized ,  placebo-controlled  , double-blind , 12-mo intervention studies in Danish ( 55 ° N ) and Finnish ( 60 ° N ) girls ( n = 144 ; mean age : 11.3 y ; mean vitamin D intake : 3.7 μg/d ) at vitamin D(3 ) supplementation amounts of 0 , 5 , and 10 μg/d were used . Serum 25(OH)D was measured with an HPLC assay in a central ized laboratory . RESULTS Clear dose-related increments ( P < 0.0001 ) in serum 25(OH)D with increasing supplemental vitamin D(3 ) were observed . The slope of the relation between vitamin D intake and serum 25(OH)D at the end of winter was 2.43 nmol ⋅ L(-1 ) ⋅ μg intake(-1 ) , and no difference in the slopes between Finnish and Danish girls was observed . The vitamin D intakes that maintained serum 25(OH)D concentrations at > 25 , > 37.5 , and > 50 nmol/L in 97.5 % of the sample were 8.3 , 13.5 , and 18.6 μg/d , respectively , whereas an intake of 6.3 μg/d maintained a serum 25(OH)D concentration > 40 nmol/L in 50 % of the sample . CONCLUSION The vitamin D intakes required to ensure that adequate vitamin D status [ defined variably as serum 25(OH)D > 25 and > 50 nmol/L ] is maintained during winter in the vast majority ( > 97.5 % ) of adolescent girls ( mean age : 11.3 y ) at northern latitudes ( > 55 ° N ) are 8.3 and 18.6 μg/d , respectively . This trial was registered at clinical trials.gov as NCT00267540 BACKGROUND AND OBJECTIVES Vitamin D3 ( cholecalciferol ) dose required to maintain sufficiency in non- Caucasian women with postmenopausal osteoporosis ( PMO ) inthe tropics has not been well studied . Some guidelines m and ate 800 - 1000 IU vitamin D/day but the Endocrine Society ( US ) advocates 1500 - 2000 IU/day to maintain 25-hydroxyvitamin-D ( 25(OH)D ) concentration at > 75 nmol/L. We aim ed to establish oral cholecalciferol dose required to maintain 25(OH)D concentration at > 75 nmol/L in PMO Chinese Malaysian women , postulating lower dose requirements amongst light-skinned subjects in the tropics . METHODS AND STUDY DESIGN 90 Chinese Malaysian PMO women in Kuala Lumpur , Malaysia ( 2 ° 30'N ) with baseline serum 25(OH)D levels > = 50 nmol/L were recruited . Prior vitamin D supplements were discontinued and subjects r and omized to oral cholecalciferol 25,000 IU/4-weekly ( Group-A ) or 50,000 IU/4-weekly ( Group- B ) for 16 weeks , administered under direct observation . Serum 25(OH)D , PTH , serum/urinary calcium were measured at baseline , 8 and 16 weeks . RESULTS Baseline characteristics , including osteoporosis severity , sun exposure ( ~3 hours/week ) , and serum 25(OH)D did not differ between treatment arms . After 16 weeks , 91 % of women sufficient at baseline , remained sufficient on 25,000 IU/4-weekly compared with 97 % on 50,000 IU/4-weekly with mean serum 25(OH)D 108.1±20.4 and 114.7±18.4 SD nmol/L respectively ( p=0.273 ) . At trial 's end , 39 % and 80 % of insufficient women at baseline attained sufficiency in Group A and Group B ( p=0.057 ) . Neither dose was associated with hyperparathyroidism or toxicity . CONCLUSIONS Despite pretrial vitamin D supplementation and adequate sun exposure , 25.6 % Chinese Malaysian PMO women were vitamin D insufficient indicating sunshine alone can not ensure sufficiency in the tropics . Both ~900 IU/day and ~1800 IU/day cholecalciferol can safely maintain vitamin D sufficiency in > 90 % of Chinese Malaysian PMO women . Higher doses are required with baseline concentration < 75 Background Vitamin D deficiency is common in the general public and athletic population s and may impair skeletal muscle function . We therefore assessed the effects of vitamin D3 supplementation on serum 25[OH]D concentrations and physical performance . Methods 30 club-level athletes were block r and omised ( using baseline 25[OH]D concentrations ) into one of three groups receiving either a placebo ( PLB ) , 20 000 or 40 000 IU/week oral vitamin D3 for 12 weeks . Serum 25[OH]D and muscle function ( 1-RM bench press and leg press and vertical jump height ) were measured presupplementation , 6 and 12 weeks postsupplementation . Vitamin D deficiency was defined in accordance with the US Institute of Medicine guideline ( < 50 nmol/l ) . Results 57 % of the subject population were vitamin D deficient at baseline ( mean±SD value 51±24 nmol/l ) . Following 6 and 12 weeks supplementation with 20 000 IU ( 79±14 and 85±10 nmol/l , respectively ) or 40 000 IU vitamin D3 ( 98±14 and 91±24 nmol/l , respectively ) , serum vitamin D concentrations increased in all participants , with every individual achieving concentrations greater than 50 nmol/l . In contrast , vitamin D concentration in the PLB group decreased at 6 and 12 weeks ( 37±18 and 41±22 nmol/l , respectively ) . Increasing serum 25[OH]D had no significant effect on any physical performance parameter ( p>0.05 ) . Conclusions Both 20 000 and 40 000 IU vitamin D3 supplementation over a 6-week period elevates serum 25[OH]D concentrations above 50 nmol/l , but neither dose given for 12 weeks improved our chosen measures of physical performance Background Interpretation of  serum vitamin D biomarkers  across pregnancy is complex due to limited underst and ing of pregnancy adaptations in vitamin D metabolism . During pregnancy , both gestational age and serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations may influence the concentrations of 1,25-dihydroxyvitamin D [ 1,25(OH)2D ] , 24,25-dihydroxyvitamin D [ 24,25(OH)2D ] , and parathyroid hormone ( PTH ) . Objective We aim ed to identify predictors of change in serum 25(OH)D across gestation in pregnant adolescents and to assess the contribution made by cholecalciferol ( vitamin D3 ) supplementation . We sought to determine whether gestational age and 25(OH)D concentration interacted to affect serum 1,25(OH)2D , 24,25(OH)2D , or PTH . Methods Pregnant adolescents ( n = 78 , 59 % African American , mean ± SD age : 17 ± 1 y ) living in Rochester , NY ( latitude 43 ° N ) were supplemented with 200 IU or 2000 IU vitamin D3/d and allowed to continue their daily prenatal supplement that contained 400 IU vitamin D3 . Serum was collected at study entry ( 18 ± 5 wk of gestation ) , halfway through study participation , and at delivery ( 40 ± 2 wk ) . Serum concentrations of the biochemical markers were modeled with linear mixed-effects regression models . Results Vitamin D3 supplement intake and season of delivery determined change in 25(OH)D across pregnancy . Fall-winter delivery was associated with a decline in 25(OH)D unless vitamin D3 supplement intake was > 872 IU/d . The interaction of gestational age and 25(OH)D affected 24,25(OH)2D concentrations . For a given 25(OH)D concentration , model-predicted serum 24,25(OH)2D increased across gestation except when 25(OH)D was < 13 ng/mL. Below this threshold , 24,25(OH)2D was predicted to decline over time . Mean serum 1,25(OH)2D was elevated ( > 100 pg/mL ) throughout the study . Conclusion Our results suggest that when maternal serum 25(OH)D was low , its catabolism into 24,25(OH)2D decreased or remained stable as pregnancy progressed in order to maintain persistently elevated serum 1,25(OH)2D . Furthermore , in adolescents living at latitude 43 ° N , st and ard prenatal supplementation did not prevent a seasonal decline in 25(OH)D during pregnancy . This study was registered at clinical trials.gov as NCT01815047 Vitamin D metabolism in elderly individuals can be compromised by several mechanisms . We previously described reduced concentrations of 1,25-dihydroxyvitamin D [ 1,25(OH)2D ] in 30 % of elderly nursing home residents . The present study assesses the effect of vitamin D supplementation on 25-hydroxyvitamin D [ 25(OH)D ] and 1,25(OH)2D . We performed a double-blind study in which 30 elderly nursing home residents were r and omly given either 50 micrograms vitamin D or a placebo daily for 6 wk . Vitamin D metabolites , immunometrically assayed parathyroid hormone ( IRMA-PTH ) , ionized calcium , and bone Gla hormone ( BGP ) were measured in serum at baseline and biweekly for 6 wk . Serum 25(OH)D concentrations increased significantly ( P less than 0.0001 ) over the 6 wk in the treatment group but were unchanged in the placebo group . Serum 1,25(OH)2D , ionized calcium , BGP , and PTH were not significantly altered by the supplement . We conclude that vitamin D supplementation results in an increase in circulating 25(OH)D but not 1,25(OH)2D ; however , the long-term effect on bone mineral metabolism remains unclear Introduction Optimal vitamin D status promotes skeletal health and is recommended with specific treatment in individuals at high risk for fragility fractures . A growing body of literature has provided indirect and some direct evidence for possible extraskeletal vitamin D-related effects . Purpose and Methods Members of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis have review ed the main evidence for possible proven benefits of vitamin D supplementation in adults at risk of or with overt chronic extra-skeletal diseases , providing recommendations and guidelines for future studies in this field . Results and conclusions Robust mechanistic evidence is available from in vitro studies and in vivo animal studies , usually employing cholecalciferol , calcidiol or calcitriol in pharmacologic rather than physiologic doses . Although many cross-sectional and prospect i ve association studies in humans have shown that low 25-hydroxyvitamin D levels ( i.e. , < 50 nmol/L ) are consistently associated with chronic diseases , further strengthened by a dose-response relationship , several meta-analyses of clinical trials have shown contradictory results . Overall , large r and omized controlled trials with sufficient doses of vitamin D are missing , and available small to moderate-size trials often included people with baseline levels of serum 25-hydroxyvitamin D levels  > 50 nmol/L , did not simultaneously assess multiple outcomes , and did not report overall safety ( e.g. , falls ) . Thus , no recommendations can be made to date for the use of vitamin D supplementation in general , parental compounds , or non-hypercalcemic vitamin D analogs in the prevention and treatment of extra-skeletal chronic diseases . Moreover , attainment of serum 25-hydroxyvitamin D levels well above the threshold desired for bone health can not be recommended based on current evidence , since safety has yet to be confirmed . Finally , the promising findings from mechanistic studies , large cohort studies , and small clinical trials obtained for autoimmune diseases ( including type 1 diabetes , multiple sclerosis , and systemic lupus erythematosus ) , cardiovascular disorders , and overall reduction in mortality require further confirmation Summary Treatment of vitamin D deficiency for 3 months with oral cholecalciferol 5,000 IU daily was more effective than 2,000 IU daily in achieving optimal serum 25-hydroxyvitamin D ( 25OHD ) concentrations . Optimal 25OHD serum level calculated to be 63.8 nmol/L. All parameters of muscle strength improved following administration of cholecalciferol for 3 months . Introduction The aim of this study was to determine the optimal dose of cholecalciferol required to achieve target serum 25OHD level ≥75 nmol/L and its relationship to both bone turnover and muscle strength . Methods Thirty deficient patients ( serum 25OHD ≤50 nmol/L ) were r and omly assigned into two groups — i.e . 2,000 and 5,000 IU/day . Data were collected at baseline , at 2 and 3 months post-therapy : ( a ) clinical demographics , ( b ) dietary calcium recall , ( c ) physical tests of muscle function and ( d ) biochemistry . Statistical analysis used paired student t test and analysis of variance . Regression analysis was used to determine relationship between serum 25OHD and parathyroid hormone ( PTH ) . Results Twenty-six ( 87 % ) patients completed 3 months of therapy . The percent increase in serum 25OHD ( compared to baseline ) was 82.7 % in 2,000-IU group and 219.5 % in 5,000-IU group . All participants ( 100 % ) achieved a serum 25OHD concentration > 50 nmol/L ; only 5 subjects ( 45.4 % ) in 2,000-IU group compared to 14 subjects ( 93.3 % ) in 5,000-IU group achieved final 25OHD concentration ≥75 nmol/L ( p < 0.01 ) . In the regression analysis , the reflexion point at which the PTH level increased above the normal range was calculated to be 63.8 nmol/L 25OHD . All parameters of muscle strength showed trends in improvements following the administration of both the 2,000 and 5,000 IU doses . No patient reported untoward side effects and no patient developed hypercalcaemia . Conclusion Treatment for 3 months with oral cholecalciferol 5,000 IU daily may be more effective than 2,000 IU daily in achieving optimal serum 25OHD concentrations in vitamin D-deficient patients Background / Objectives : To assess the prevalence of vitamin D deficiency in Dutch athletes and to define the required dosage of vitamin D3 supplementation to prevent vitamin D deficiency over the course of a year . Subjects/ Methods : Blood sample s were collected from 128 highly trained athletes to assess total 25(OH)D concentration . Of these 128 athletes , 54 male and 48 female athletes ( 18–32 years ) were included in a r and omized , double blind , dose – response study . Athletes with either a deficient ( < 50 nmol/l ) or an insufficient ( 50–75 nmol/l ) 25(OH)D concentration were r and omly assigned to take 400 , 1100 or 2200 IU vitamin D3 per day orally for 1 year . Athletes who had a total 25(OH)D concentration above 75 nmol/l at baseline continued with the study protocol without receiving vitamin D supplements  . Serum total 25(OH)D concentration was assessed every 3 months , as well as  dietary vitamin D intake and sunlight exposure . Results : Nearly 70 % of all athletes showed an insufficient ( 50–75 nmol/l ) or a deficient ( < 50 nmol/l ) 25(OH)D concentration at baseline . After 12 months , serum 25(OH)D concentration had increased more in the 2200 IU/day group ( + 50±27 nmol/l ) than the sufficient group receiving no supplements ( + 4±17 nmol/l ; P<0.01 ) and the 1100 IU/day group ( + 25±23 nmol/l ; P<0.05 ) . Supplementation with 2200 IU/day vitamin D result ed in a sufficient 25(OH)D concentration in 80 % of the athletes after 12 months . Conclusions : Vitamin D deficiency is highly prevalent in athletes . Athletes with a deficient or an insufficient 25(OH)D concentration can achieve a sufficient 25(OH)D concentration within 3 months by taking 2200 IU/day BACKGROUND It is unclear whether and at what dose vitamin D supplementation affects insulin resistance ( IR ) . OBJECTIVE We sought to investigate whether vitamin D at doses higher than currently recommended decreases indexes of IR in an ambulatory population of overweight elderly subjects . DESIGN This double-blind , r and omized , controlled multicenter trial enrolled 257 elderly overweight individuals aged ≥65 y with baseline 25-hydroxyvitamin D [ 25(OH)D ] concentrations between 10 and 30 ng/mL. All subjects received 1000 mg calcium citrate/d , with vitamin D administered weekly at an equivalent dose of 600 or 3750 IU/d . The homeostasis model assessment ( HOMA ) of IR index at 1 y was the primary outcome . We also assessed the McAuley index . RESULTS In total , 222 subjects ( 55 % women ) with a mean ± SD age and body mass index ( BMI ; in kg/m(2 ) ) of 71 ± 4 y and 30 ± 4 , respectively , completed the study . Subjects ' baseline characteristics , including IR indexes , were similar across groups : 69 % had prediabetes , 54 % had hypertension ( 47 % were taking antihypertensive medications ) , and 60 % had hyperlipidemia , nearly half of whom were receiving lipid-lowering drugs . At 1 y , mean ± SD serum 25(OH)D increased from 20 ± 7 to 26 ± 7 ng/mL in the low-dose arm ( P < 0.0001 ) and from 21 ± 8 to 36 ± 10 ng/mL in the high-dose arm ( P < 0.001 ) . Median HOMA-IR indexes did not change compared with baseline concentrations and were similar in the high- [ 2.2 ( IQR : 1.5 , 2.9 ) ] and low-dose [ 2.3 ( IQR : 1.6 , 3.3 ] treatment groups . Adjusted analyses showed that HOMA-IR was predicted by the baseline HOMA index and BMI but not by vitamin D dose , baseline serum 25(OH)D , or change in 25(OH)D.  CONCLUSION Vitamin D3 at 3750 IU/d did not improve HOMA-IR compared with the Institute of Medicine Recommended Dietary Allowance of 600 IU/d in elderly overweight individuals . This trial was registered at clinical trials.gov as NCT01315366 IMPORTANCE Vitamin D supplementation in infancy is required to support healthy bone mineral accretion . A supplement of 400 IU of vitamin D per day is thought to support plasma 25-hydroxyvitamin D ( 25[OH]D ) concentrations between 40 and 50 nmol/L ; some advocate 75 to 150 nmol/L for bone health . OBJECTIVE To investigate the efficacy of different dosages of vitamin D in supporting 25(OH)D concentrations in infants . DESIGN , SETTING , AND PARTICIPANTS Double-blind r and omized clinical trial conducted among 132 one-month-old healthy , term , breastfed infants from Montréal , Québec , Canada , between March 2007 and August 2010 . Infants were followed up for 11 months ending August 2011 ( 74 % completed study ) . INTERVENTION Participants were r and omly assigned to receive oral cholecalciferol ( vitamin D3 ) supplements of 400 IU/d ( n=39 ) , 800 IU/d ( n=39 ) , 1200 IU/d ( n=38 ) , or 1600 IU/d ( n=16 ) . MAIN OUTCOMES AND MEASURES The primary outcome was a plasma 25(OH)D concentration of 75 nmol/L or greater in 97.5 % of infants at 3 months . Secondary outcomes included 25(OH)D concentrations of 75 nmol/L or greater in 97.5 % of infants at 6 , 9 , and 12 months ; 25(OH)D concentrations of 50 nmol/L or greater across all times ; growth ; and whole body and regional bone mineral content . Data were analyzed by intention to treat using available data , logistic regression , and mixed-model analysis of variance . RESULTS By 3 months , 55 % ( 95 % CI , 38%-72 % ) of infants in the 400-IU/d group achieved a 25(OH)D concentration of 75 nmol/L or greater vs 81%(95 % CI , 65%-91 % ) in the 800-IU/d group , 92 % ( 95 % CI , 77%-98 % ) in the 1200-IU/d group , and 100 % in the 1600-IU/d group . This concentration was not sustained in 97.5 % of infants at 12 months in any of the groups . The 1600-IU/d dosage was discontinued prematurely because of elevated plasma 25(OH)D concentrations . All dosages established 25(OH)D concentrations of 50 nmol/L or greater in 97 % ( 95 % CI , 94%-100 % ) of infants at 3 months and sustained this in 98 % ( 95 % CI , 94%-100 % ) to 12 months . Growth and bone mineral content did not differ by dosage . CONCLUSIONS AND RELEVANCE Among healthy , term , breastfed infants , only a vitamin D supplement dosage of 1600 IU/d ( but not dosages of 400 , 800 , or 1200 IU/d ) increased plasma 25(OH)D concentration to 75 nmol/L or greater in 97.5 % of infants at 3 months . However , this dosage increased 25(OH)D concentrations to levels that have been associated with hypercalcemia . TRIAL REGISTRATION clinical trials.gov Identifier : NCT00381914 Fortification of foods is a feasible way of preventing low vitamin D status .  Bread could be a suitable vehicle for fortification because it is a common part of diets worldwide . The bioavailability of cholecalciferol from bread is not known . We studied cholecalciferol stability , the concentration of the added cholecalciferol , the dispersion of cholecalciferol in bread , and the bioavailability of cholecalciferol from fortified bread . Three batches of fortified low-fiber wheat and high-fiber rye breads were baked ; from each batch , 3 sample s of dough and bread were analyzed for their cholecalciferol content . In a single-blind bioavailability study , 41 healthy women , 25 - 45 y old , with mean serum 25-hydroxyvitamin D concentration 29 nmol/L ( range 12 - 45 nmol/L ) , were r and omly assigned to 4 study groups . Each group consumed fortified wheat bread , fortified rye bread , regular wheat bread ( control ) , or regular wheat bread and a cholecalciferol supplement ( vitamin D control ) daily for 3 wk . The daily dose of vitamin D was 10 mug in all groups except the control group . The vitamin dispersed evenly in the breads and was stable . Both fortified breads increased serum 25-hydroxyvitamin D concentration as effectively as the cholecalciferol supplement . Supplementation or fortification did not affect serum intact parathyroid hormone concentration or urinary calcium excretion . In conclusion , fortified bread is a safe and feasible way to improve vitamin D nutrition BACKGROUND Eczema is one of the most common chronic inflammatory skin diseases , affecting about 20 % of children . The pathogenic mechanisms of eczema are still not fully understood , and current treatment of moderate-severe eczema is often difficult . Recently , it has been suggested that Vitamin D plays a key role in this disease , even if mechanisms are only partially known . OBJECTIVE The purpose of our study was to assess the  25-Hydroxyvitamin D serum levels in a pediatric population suffering from chronic eczema ( IgE-mediated and non-IgE-mediated ) , and to correlate these phenotypes with the SCORAD severity and selected clinical and biological parameters . Moreover , we aim ed to evaluate whether a supplementation of Vitamin D3 could affect the same clinical and laboratory parameters . METHODS 89 children with chronic eczema were enrolled in the study . Severity of eczema was assessed with the SCORAD index . Past and present history was taken , and patients were divided into two groups according to the state of sensitization . According to a r and omization schedule , the enrolled children were assigned to the following groups : supplementation group , which received a daily oral Vitamin D3 supplementation ( 2000 IUs ) for 3 months ; control group which received no supplementation . RESULTS  Vitamin D concentrations in patients with moderate and severe eczema were not statistically different from Vitamin D concentration detected in the serum of patients with mild eczema . Furthermore , we did not find any correlation between Vitamin D levels , total IgEs and SCORAD index , both in the Sensitized and in the Not-Sensitized group . The Vitamin D3 supplementation did not influence the SCORAD severity or the total IgEs concentration . CONCLUSION To our knowledge , our study is the first one that shows no correlation between serum levels of Vitamin D , eczema severity and IgE sensitization in a pediatric population suffering from chronic eczema CONTEXT Dosages of vitamin D necessary to prevent or treat vitamin D deficiency in children remain to be clarified . OBJECTIVE To determine the effects of vitamin D3 1000 IU/d on serum 25-hydroxyvitamin D [ 25(OH)D ] , PTH , and markers of bone turnover ( osteocalcin and collagen type 1 cross-linked C-telopeptide ) in black children and white children , and to explore whether there is a threshold level of 25(OH)D associated with maximal suppression of serum PTH concentration . DESIGN Healthy 8- to 14-year-old Pittsburgh-area black ( n = 84 ) and white ( n = 73 ) children not receiving vitamin supplements , enrolled from October through March from 2008 through 2011 , were r and omized to vitamin D3 1000 IU or placebo daily for 6 months . RESULTS The mean baseline concentration of 25(OH)D was < 20 ng/mL in both the vitamin D-supplemented group and the placebo group ( 19.8 ± 7.6 and 18.8 ± 6.9 ng/mL , respectively ) . The mean concentration was higher in the supplemented group than in the placebo group at 2 months ( 26.4 ± 8.1 vs 18.9 ± 8.1 ng/mL ; P < .0001 ) and also at 6 months ( 26.7 ± 7.6 vs 22.4 ± 7.3 ; P = .003 ) , after adjusting for baseline 25(OH)D , race , gender , pubertal status , dietary vitamin D intake , body mass index , and sunlight exposure . Increases were only significant in black children , when examined by race . The association between 25(OH)D and PTH concentrations was inverse and linear , without evidence of a plateau . Overall , vitamin D supplementation had no effect on PTH and bone turnover  . CONCLUSIONS Vitamin D3 supplementation with 1000 IU/d in children with mean baseline 25(OH)D concentration < 20 ng/mL effectively raised their mean 25(OH)D concentration to ≥20 ng/mL but failed to reach 30 ng/mL.  Vitamin D supplementation had no effect on PTH concentrations Background Mood disorders in pregnancy and post-partum period are common and considered as a public health issue . Research ers have studied the relationship between low serum vitamin D concentration and perinatal depression , although no clinical trial has been conducted on vitamin D ’s effects on depression related to childbirth . This study evaluated the effect of vitamin D3 supplementation on perinatal depression scores . Methods This r and omized clinical trial was done in pregnant women who were under prenatal care in a teaching hospital in Shiraz , Iran . The inclusion criteria were : being 18 years or older , no history of mental illness and internal diseases , a singleton live fetus , without any pregnancy complications , gestational age of 26–28 weeks upon enrollment , and depression score of 0 to 13 . The Edinburgh Postnatal Depression scale was used to evaluate depression scores . A total of 169 participants were assigned to the two groups of placebo and vitamin D through block r and omization design . Vitamin D group received 2000 IU vitamin D3 daily from 26 to 28 weeks of gestation until childbirth . Maternal serum 25-hydroxyvitamin D concentrations were measured at baseline and childbirth . Besides , depression scores were evaluated four times : at 26–28 and 38–40 weeks of gestation , and finally at 4 and 8 weeks after birth . Results The two groups were similar in relation to baseline 25-hydroxyvitamin D concentrations . However , at childbirth , the vitamin D group had significantly higher 25-hydroxyvitamin D concentration in comparison to the control group ( p < 0.001 ) . At baseline , no correlation was observed between 25-hydroxyvitamin D concentration and depression score ( r = 0.13 , p = 0.09 ) . There was no significant difference between the two study groups in relation to the baseline depression score . While , the vitamin D group had greater reduction in depression scores than the control group at 38–40 weeks of gestation ( p = 0.01 ) also , at 4 and 8 weeks after birth ( p < 0.001 ) . Conclusions The present trial showed that consuming 2000 IU vitamin D3 daily during late pregnancy was effective in decreasing perinatal depression levels . We suggest further clinical trial in pregnant mothers who are at risk for postnatal depression . Trial registration Iranian Registry of Clinical Trials I RCT 2015020310327N11 . Date of registration : March 9th 2015 CONTEXT Vitamin D insufficiency/deficiency is commonly observed in black youth . OBJECTIVE The aim was to determine 25-hydroxyvitamin D [ 25(OH)D ] in response to 2000 IU vitamin D supplementation over time ; to evaluate the relation between 25(OH)D concentrations and total body fat mass by dual-energy x-ray absorptiometry ; and to determine whether vitamin D supplementation improves arterial stiffness measured by pulse wave velocity ( PWV ) . DESIGN We conducted a r and omized , blinded , controlled clinical trial . SETTING AND PARTICIPANTS Forty-nine normotensive black boys and girls , aged 16.3 ± 1.4 yr , were r and omly assigned to either the control group ( 400 IU/d ; n = 24 ) or the experimental group ( 2000 IU/d ; n = 25 ) . RESULTS Plasma 25(OH)D values at baseline and at 4 , 8 , and 16 wk were 34.0 ± 10.6 , 44.9 ± 9.4 , 51.2 ± 11.1 , and 59.8 ± 18.2 nmol/liter , respectively , for the control group ; and 33.1 ± 8.7 , 55.0 ± 11.8 , 70.9 ± 22.0 , and 85.7 ± 30.1 nmol/liter , respectively , for the experimental group . The experimental group vs. the control group reached significantly higher 25(OH)D concentrations at 8 and 16 wk , respectively . Partial correlation analyses indicated that total body fat mass at baseline was significantly and inversely associated with 25(OH)D concentrations in response to the 2000-IU supplement across time . Furthermore , carotid-femoral PWV increased from baseline ( 5.38 ± 0.53 m/sec ) to posttest ( 5.71 ± 0.75 m/sec ) in the control group ( P = 0.016 ) , whereas in the experimental group carotid-femoral PWV decreased from baseline ( 5.41 ± 0.73 m/sec ) to posttest ( 5.33 ± 0.79 m/sec ) ( P = 0.031 ) . CONCLUSION Daily 2000 IU vitamin D supplementation may be effective in optimizing vitamin D status and counteracting the progression of aortic stiffness in black youth . Plasma 25(OH)D concentrations in response to the 2000 IU/d supplementation are negatively modulated by adiposity Purpose While vitamin D is critical for optimal skeletal health , it also appears to play a significant role in vascular homeostasis . This pilot study compared arteriovenous ( AV ) access outcomes following cholecalciferol supplementation compared to placebo in end-stage renal disease patients preparing to undergo AV access creation . Methods A total of 52 adult hemodialysis patients preparing for arteriovenous fistula ( AVF ) creation were r and omized to receive perioperative high-dose cholecalciferol versus placebo in this double-blind , r and omized , placebo-controlled pilot study . The primary outcome was mean response to high-dose oral cholecalciferol versus placebo , and secondary outcome AV access maturation at 6 months . Logistic regression was used to assess the association between AV access maturation and baseline , posttreatment and overall change in vitamin D concentration . Results A total of 45 % of cholecalciferol-treated and 54 % of placebo-treated patients were successfully using their AVF or arteriovenous graft ( AVG ) at 6 months ( p=0.8 ) . Baseline serum concentrations of 25(OH)D and 1,25(OH)2D did not differ between those who experienced AVF or AVG maturation and those who did not ( p=0.22 and 0.59 , respectively ) . Similarly , there was no relationship between AVF or AVG maturation and posttreatment serum 25(OH)D and 1,25(OH)2D concentration ( p=0.24 and 0.51 , respectively ) . Conclusions Perioperative high-dose vitamin D3 therapy does correct 25(OH)D level but does not appear to have an association with AV access maturation rates . Future research may include extended preoperative vitamin D3 therapy in a larger population or in certain sub population s at high risk for AVF failure BACKGROUND Serum 25-hydroxyvitamin D ( 25-[OH]D ) is considered the best biomarker of clinical vitamin D status . OBJECTIVE To determine the effect of increasing oral doses of vitamin D(3 ) on serum 25-(OH)D and serum parathyroid hormone ( PTH ) levels in postmenopausal white women with vitamin D insufficiency ( defined as a 25-[OH]D level ≤50 nmol/L ) in the presence of adequate calcium intake . These results can be used as a guide to estimate the Recommended Dietary Allowance ( RDA ) ( defined as meeting the needs of 97.5 % of the population ) for vitamin D(3 ) . DESIGN R and omized , placebo-controlled trial . ( Clinical Trials.gov registration number : NCT00472823 ) SETTING Creighton University Medical Center , Omaha , Nebraska . PARTICIPANTS 163 healthy postmenopausal white women with vitamin D insufficiency enrolled in the winter or spring of 2007 to 2008 and followed for 1 year . INTERVENTION Participants were r and omly assigned to receive placebo or vitamin D(3 ) , 400 , 800 , 1600 , 2400 , 3200 , 4000 , or 4800 IU once daily . Daily calcium supplements were provided to increase the total daily calcium intake to 1200 to 1400 mg . MEASUREMENTS The primary outcomes were 25-(OH)D and PTH levels at 6 and 12 months . RESULTS The mean baseline 25-(OH)D level was 39 nmol/L. The dose response was curvilinear and tended to plateau at approximately 112 nmol/L in patients receiving more than 3200 IU/d of vitamin D(3 ) . The RDA of vitamin D(3 ) to achieve a 25-(OH)D level greater than 50 nmol/L was 800 IU/d . A mixed-effects model predicted that 600 IU of vitamin D(3 ) daily could also meet this goal . Compared with participants with a normal body mass index ( < 25 kg/m(2 ) ) , obese women ( ≥30 kg/m(2 ) ) had a 25-(OH)D level that was 17.8 nmol/L lower . Parathyroid hormone levels at 12 months decreased with an increasing dose of vitamin D(3 ) ( P = 0.012 ) . Depending on the criteria used , hypercalcemia occurred in 2.8 % to 9.0 % and hypercalciuria in 12.0 % to 33.0 % of participants ; events were unrelated to dose . LIMITATION Findings may not be generalizable to other age groups or persons with substantial comorbid conditions . CONCLUSION A vitamin D(3 ) dosage of 800 IU/d increased serum 25-(OH)D levels to greater than 50 nmol/L in 97.5 % of women ; however , a model predicted the same response with a vitamin D(3 ) dosage of 600 IU/d . These results can be used as a guide for the RDA of vitamin D(3 ) , but prospect i ve trials are needed to confirm the clinical significance of these results . PRIMARY FUNDING SOURCE National Institute on Aging Background Antenatal vitamin D status may be associated with the risk of adverse pregnancy and neonatal outcomes ; however , the benefits of vitamin D supplementation during pregnancy remain unknown . Methods We conducted a double-blind placebo-controlled r and omized trial to evaluate the effect of high-dose prenatal 3rd trimester vitamin D3 supplementation on maternal and neonatal ( cord blood ) serum 25-hydroxyvitamin D ( 25(OH)D ) concentration ( primary biochemical efficacy outcome ) and maternal serum calcium concentration ( primary safety measure ) . Eligibility criteria were pregnant women aged 18 to < 35 years , at 26 to 29 weeks gestation , and residing in Dhaka , Bangladesh . 160 women were r and omized by 1:1 allocation to one of two parallel intervention groups ; placebo ( n = 80 ) or 35,000 IU/week of vitamin D3 ( n = 80 ) until delivery . All participants , study personnel and study investigators were blind to treatment allocation . Results Mean maternal 25(OH)D concentration was similar in the vitamin D and placebo groups at baseline ( 45 vs. 44 nmol/L ; p = 0.66 ) , but was significantly higher in the vitamin D group vs. placebo group among mothers at delivery ( 134 vs. 38 nmol/L ; p < 0.001 ) and newborns ( cord blood : 103 vs. 39 ; p < 0.001 ) . In the vitamin D group , 95 % of neonates and 100 % of mothers attained 25(OH)D > 50 nmol/L , versus 21 % mothers and 19 % of neonates in the placebo group . No participants met criteria for hypercalcemia , there were no known supplement-related adverse events , and major pregnancy outcomes were similar between groups . Conclusions Antenatal 3rd-trimester vitamin D3 supplementation ( 35,000 IU/week ) significantly raised maternal and cord serum 25(OH)D concentrations above 50 nmol/L in almost all participants without inducing hypercalcemia or other observed safety concerns . Doses up to 35,000 IU/week may be cautiously used in further research aim ed at establishing the clinical effects and safety of vitamin D3 supplementation in pregnancy . Trial registration This trial was registered at Clinical Trials.gov ( NCT01126528 ) Vitamin D insufficiency and deficiency are common in the elderly . Most previous studies using alendronate have used vitamin D supplementation regardless of individual vitamin D status . However , the minimum required vitamin D levels for the efficacy of alendronate treatment of osteoporosis remain unclear . Fifty-two postmenopausal women , diagnosed with osteoporosis , were enrolled in this prospect i ve study , in which they took 5 mg of alendronate daily for 6 months without any supplements . Associations between baseline factors and their changes during the treatment and the change in the lumbar spine bone mineral density ( LS-BMD ) were examined . The most appropriate cut-off level of 25-hydroxyvitamin D ( 25[OH]D ) for the optimal increase in LS-BMD with alendronate was determined using the Akaike information criterion statistical criterion . Overall , alendronate treatment significantly increased LS-BMD by 4.7 % . The basal serum 25(OH)D and change in urinary NTX were significantly associated with the increase in LS-BMD . The increase in LS-BMD between the two groups was not different when comparing those with baseline 25(OH)D above vs. below 30 ng/ml . However , 25(OH)D of 25 ng/ml was determined to be the minimum required vitamin D level for an adequate effect of alendronate . Vitamin D status may affect the increase in LS-BMD with alendronate treatment in individuals being treated for osteoporosis , and a 25(OH)D level > 25 ng/ml appears to be required for an optimal LS-BMD response BACKGROUND Adolescents are a population group at high risk of low vitamin D status , yet the evidence base for establishing dietary vitamin D requirements remains weak . OBJECTIVE The aim was to establish the distribution of  vitamin D intakes required to maintain serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations above proposed cutoffs ( 25 , 30 , 40 , and 50 nmol/L ) during winter in white males and females ( 14 - 18 y of age ) in the United Kingdom ( 51 ° N ) . DESIGN In a dose-response trial , 110 adolescents ( aged 15.9 ± 1.4 y ; 43 % males ) were r and omly assigned to receive 0 , 10 , or 20 μg vitamin D3 supplements/d for 20 wk during winter . A nonlinear regression model was fit to total vitamin D intake and postintervention serum 25(OH)D concentrations , and regression-predicted values estimated the vitamin D intakes required to maintain serum 25(OH)D concentrations above specific cutoffs . RESULTS Mean ± SD serum 25(OH)D concentrations increased from 49.2 ± 12.0 to 56.6 ± 12.4 nmol/L and from 51.7 ± 13.4 to 63.9 ± 10.6 nmol/L in the 10- and 20-μg/d groups , respectively , and decreased in the placebo group from 46.8 ± 11.4 to 30.7 ± 8.6 nmol/L ( all P ≤ 0.001 ) . Vitamin D intakes required to maintain 25(OH)D concentrations > 25 and > 30 nmol/L in 97.5 % of adolescents were estimated to be 10.1 and 13.1 μg/d , respectively , and 6.6 μg/d to maintain 50 % of adolescents at concentrations > 40 nmol/L. Because the response of 25(OH)D reached a plateau at 46 nmol/L , there is uncertainty in estimating the vitamin D intake required to maintain 25(OH)D concentrations > 50 nmol/L in 97.5 % of adolescents , but it exceeded 30 μg/d . CONCLUSION Vitamin D intakes between 10 and ∼30 μg/d are required by white adolescents during winter to maintain serum 25(OH)D concentrations > 25 - 50 nmol/L , depending on the serum 25(OH)D threshold chosen . This trial was registered at clinical trials.gov as NCT02150122 and as International St and ard R and omized Controlled Trial Number IS RCT N40736890 INTRODUCTION The exact amount of vitamin D required for pregnant women to adequately supply the foetus during pregnancy is still unclear . This r and omised trial attempted to determine the optimal dose of vitamin D necessary during pregnancy in order to attain a vitamin D level > 20 ng/mL in neonates . METHODS A total of 51 healthy , pregnant women in Yazd , Iran , were recruited in 2009 . Of these , 34 were r and omised to receive either 50,000 IU ( Group A ) or 100,000 IU ( Group B ) of vitamin D3 per month from the second trimester of pregnancy . The remaining 17 pregnant women , who formed the third group ( Group C ) and were found to have vitamin D deficiency , were initially treated with 200,000 IU of vitamin D3 , following which the dose was adjusted to 50,000 IU per month . 25-hydroxyvitamin D ( 25[OH]D ) in cord blood was measured by chemiluminescence immunoassay , and a serum 25(OH)D level < 20 ng/mL was defined as deficiency . RESULTS All the pregnant women had a vitamin D level < 30 ng/mL at the beginning of the second trimester . The neonates of 76 % of women from Group A had sufficient levels of 25(OH)D. All the neonates born to women in Groups B and C had 25(OH)D > 20 ng/mL. No side effects were observed in our participants during the period of vitamin D supplementation . CONCLUSION A vitamin D3dose > 50,000 IU/month is required during the second and third trimesters of pregnancy for vitamin D-deficient pregnant women in order for their neonates to achieve serum 25(OH)D levels > 20 ng/mL. Supplementation with < 50,000 IU/month is insufficient to ensure a vitamin D level > 20 ng/mL in all neonates born to vitamin D-deficient pregnant women OBJECTIVE : To determine the vitamin D dose necessary to achieve serum 25-hydroxyvitamin D ( 25(OH)D ) concentration ≥20 ng/mL during infancy . METHODS : A r and omized , double-blind , placebo-controlled trial in New Zeal and . Pregnant mothers , from 27 weeks ’ gestation to birth , and then their infants , from birth to age 6 months , were r and omly assigned to 1 of 3 mother/infant groups : placebo/placebo , vitamin D3 1000/400 IU , or vitamin D3 2000/800 IU . Serum 25(OH)D and calcium concentrations were measured at enrollment , 36 weeks ’ gestation , in cord blood , and in infants at 2 , 4 , and 6 months of age . RESULTS : Two-hundred- and -sixty pregnant women were r and omized . At enrollment , the proportions with serum 25(OH)D ≥20 ng/mL for placebo , lower-dose , and higher-dose groups were 54 % , 64 % , and 55 % , respectively . The proportion with 25(OH)D ≥20 ng/mL was larger in both intervention groups at 36 weeks ’ gestation ( 50 % , 91 % , 89 % , P < .001 ) . In comparison with placebo , the proportion of infants with 25(OH)D ≥20 ng/mL was larger in both intervention groups to age 4 months : cord blood ( 22 % , 72 % , 71 % , P < .001 ) , 2 months ( 50 % , 82 % , 92 % , P < .001 ) , and 4 months ( 66 % , 87 % , 87 % , P = .004 ) , but only in the higher-dose group at age 6 months ( 74 % , 82 % , 89 % , P = .07 ; higher dose versus placebo P = .03 , lower dose versus placebo P = .21 ) . CONCLUSIONS : Daily vitamin D supplementation during pregnancy and then infancy with 1000/400 IU or 2000/800 IU increases the proportion of infants with 25(OH)D ≥20 ng/mL , with the higher dose sustaining this increase for longer Scientific data pertaining to vitamin D supplementation during lactation are scarce . The daily recommended intake for vitamin D during lactation has been arbitrarily set at 400 IU/d ( 10 microg/d ) . This recommendation is irrelevant with respect to maintaining the nutritional vitamin D status of mothers and nursing infants , especially among darkly pigmented individuals . Our objective was to examine the effect of high-dose maternal vitamin D2 supplementation on the nutritional vitamin D status  of mothers and nursing infants . Fully lactating women ( n = 18 ) were enrolled at 1 mo after birth to 1 of 2 treatment arms , ie , 1600 IU vitamin D2 and 400 IU vitamin D3 ( prenatal vitamin ) or 3600 IU vitamin D2 and 400 IU vitamin D3 , for a 3-mo study period . High-dose ( 1600 or 3600 IU/d ) vitamin D2 supplementation for a period of 3 mo safely increased circulating 25-hydroxyvitamin D [ 25(OH)D ] concentrations for both groups . The antirachitic activity of milk from mothers receiving 2000 IU/d vitamin D increased by 34.2 IU/L , on average , whereas the activity in the 4000 IU/d group increased by 94.2 IU/L. Nursing infant circulating 25(OH)D2 concentrations reflected maternal intake and the amount contained in the milk . With limited sun exposure , an intake of 400 IU/d vitamin D would not sustain circulating 25(OH)D concentrations and thus would supply only limited amounts of vitamin D to nursing infants in breast milk . A maternal intake of 2000 IU/d vitamin D would elevate circulating 25(OH)D concentrations for both mothers and nursing infants , albeit with limited capacity , especially with respect to nursing infants . A maternal intake of 4000 IU/d could achieve substantial progress toward improving both maternal and neonatal nutritional vitamin D status Context Intake of hormonal contraceptives ( HC ) is associated with higher total 25-hydroxyvitamin D [ 25(OH)D ] concentrations , but the effect of HC on free 25(OH)D is unclear . Objective We investigated whether free 25(OH)D concentrations differ according to use of HC . Design This is a post hoc analysis of a r and omized open trial . Setting This study was conducted from 13 January to 9 May , 2016 , at a clinical research organization in Esslingen , Germany . Participants We included 201 apparently healthy women of childbearing age . Intervention Participants were r and omly assigned to receive a daily multimicronutrient supplement for 8 weeks ; the supplement contained 200 IU ( n = 100 ) or 800 IU ( n = 101 ) of vitamin D3 . Main Outcome Measures Primary outcome was the difference in free 25(OH)D between users and nonusers of  HC  . Results Overall , 176 participants [ median ( 25th to 75th percentiles ) age : 25 ( 22 to 29 ) years ] with available free 25(OH)D were included in the present analysis . At baseline , total 25(OH)D was significantly higher in users ( n = 110 ) than in nonusers ( n = 66 ) of HC [ 49.2 ( 33.4 to 63.4 ) vs 39.1 ( 23.8 to 52.5 ) nmol/L ; P < 0.001 ] , whereas there was no difference in free 25(OH)D [ 7.87 ( 6.50 to 10.11 ) vs 7.88 ( 6.35 to 10.12 ) pmol/L ; P = 0.923 ] . These results were confirmed after multimicronutrient supplementation and in subgroups according to treatment allocation . Conclusions Use of HC was associated with , on average , 26 % higher total 25(OH)D , whereas free 25(OH)D values did not differ according to use of HC . These findings are relevant for epidemiological studies , but the physiological implication s remain to be clarified Many people worldwide are vitamin D ( VTD ) deficient or insufficient , and there is still no consensus on the dose of VTD that should be administered to achieve a 25(OH)D concentration of 20 or 30 ng/mL. In this study , we aim ed to determine an adapted supplementation of VTD able to quickly and safely increase the vitamin D status of healthy adults with low 25(OH)D. One hundred and fifty ( 150 ) subjects were r and omized into three groups , each to receive , orally , a loading dose of 50,000 , 100,000 or 200,000 IU of VTD3 at Week 0 , followed by 25,000 , 50,000 or 100,000 IU at Week 4 and Week 8 . Whereas 25(OH)D baseline values were not different between groups ( p = 0.42 ) , a significant increase was observed at Week 12 ( p < 0.0001 ) with a mean change from baseline of 7.72 ± 5.08 , 13.3 ± 5.88 and 20.12 ± 7.79 ng/mL. A plateau was reached after eight weeks . No related adverse event was recorded . This study demonstrated a linear dose-response relationship with an increase in 25(OH)D levels proportional to the dose administered . In conclusion , a loading dose of 200,000 IU VTD3 followed by a monthly dose of 100,000 IU is the best dosing schedule to quickly and safely correct the VTD status CONTEXT The benefits of high serum levels of 25-hydroxyvitamin D [ 25(OH)D ] are unclear . Trials are needed to establish an appropriate evidence base . OBJECTIVE We plan to conduct a large-scale trial of vitamin D supplementation for the reduction of cancer incidence and overall mortality and report here the methods and results of a pilot trial established to inform its design . DESIGN Pilot D-Health was a r and omized trial carried out in a general community setting with 12 months intervention and follow-up . PARTICIPANTS Participants were 60- to 84-yr-old residents of one of the four eastern Australian states who did not have any vitamin D-related disorders and who were not taking more than 400 IU supplementary vitamin D per day . A total of 644 participants were r and omized , and 615 completed the study ( two persons withdrew because of nonserious adverse events ) . INTERVENTIONS The interventions were monthly doses of placebo or 30,000 or 60,000 IU vitamin D(3 ) . MAIN OUTCOMES The main outcomes were the recruitment rate and changes in serum 25(OH)D. RESULTS Ten percent of those approached were recruited . At baseline , the mean 25(OH)D was 42 nmol/liter in all three study arms . The mean change in 25(OH)D in the placebo group was 0.12 nmol/liter , compared with changes of 22 and 36 nmol/liter in the 30,000- and 60,000-IU groups , respectively . CONCLUSIONS The D-Health pilot has shown that a large trial is feasible in Australia and that a dose of 2000 IU/d will be needed to ensure that a large proportion of the population reaches the target serum 25(OH)D level Objective To identify the combined effect of prenatal and postnatal vitamin D3 supplementation on the vitamin D status of pregnant and lactating women and their exclusively breastfed infants . Design Double‐blind , r and omized controlled trial . Setting Upper Midwestern U.S. , hospital‐based obstetric practice . Participants Pregnant women ( N = 13 ) planning to exclusively breastfeed were r and omized at 24 to 28 weeks gestation to receive vitamin D3 at a dosage of 400 IU ( control group , n = 6 ) or 3,800 IU ( intervention group , n = 7 ) daily through 4 to 6 weeks postpartum . Vitamin D status was determined at enrollment and in mother – infant dyads at 24 to 72 hours after birth and 4 to 6 weeks postpartum . Methods Serum 25‐hydroxyvitamin D levels were measured to determine the effect of vitamin D3 supplementation on the vitamin D status of mothers and infants . Analysis of covariance was used to compare differences in 25‐hydroxyvitamin D levels between the control and intervention groups . Results The mothers ’ vitamin D levels were significantly higher in the intervention group than in the control group at birth ( p = .044 ) and at 4 to 6 weeks postpartum ( p = .002 ) . Infants in the intervention group had significantly higher vitamin D levels at birth ( p = .021 ) and nonsignificant , clinical ly relevant increases at 4 to 6 weeks of age ( p = .256 ) . No differences were found between maternal groups in serum calcium or parathyroid hormone levels . Conclusion Prenatal to postpartum vitamin D3 supplementation is an effective intervention to increase a mother ’s vitamin D status and to promote optimal vitamin D status in newborns and exclusively breastfed infants In previous studies , we demonstrated that 12-month treatment with 0.75μg/day eldecalcitol increased bone mineral density in osteoporotic patients regardless of serum 25-hydroxyvitamin D ( 25(OH)D ) level , and in a 3-year r and omized double-blind clinical trial , eldecalcitol significantly reduced the incidences of vertebral and wrist fractures compared to alfacalcidol . However , it remains unclear whether the fracture risk reduction by eldecalcitol is affected by serum 25(OH)D. In the fracture prevention trial , patients with low 25(OH)D level at baseline were supplemented with 400IU/day native vitamin D3 . In the current study , patients from that trial were divided according to the tertiles of serum 25(OH)D level at 6 months after treatment initiation . The increases in lumbar and hip BMD by eldecalcitol were significantly higher in all tertiles than those by alfacalcidol .  The incidences of vertebral and osteoporotic fractures tended to be lower in each tertile of the eldecalcitol-treated group than in the corresponding tertile of the alfacalcidol-treated group , with the exception of vertebral fractures in the low tertile . We also investigated whether eldecalcitol treatment affected levels of serum 25(OH)D , serum 1,25(OH)2D , and parathyroid hormone in patients without vitamin D supplementation .  With eldecalcitol treatment , serum 1,25(OH)2D concentration was reduced by approximately 50 % , whereas serum levels of parathyroid hormone and 25(OH)D were not affected . The major findings of the present study were that eldecalcitol did not affect serum 25(OH)D levels , and that it reduced the incidence of osteoporotic fractures and increased BMD in comparison with alfacalcidol regardless of serum 25(OH)D level within the range of serum 25(OH)D concentrations at or higher than 20ng/mL. Whether eldecalcitol is similarly effective at vitamin D deficient serum 25(OH)D levels remains to be clarified . This article is part of a Special Issue entitled ' Vitamin D Workshop ' CONTEXT AND OBJECTIVE Suboptimal vitamin D status can be corrected by vitamin D supplementation , but individual responses to supplementation vary . We aim ed to examine genetic and nongenetic determinants of change in serum 25-hydroxyvitamin D ( 25(OH)D ) after supplementation . DESIGN AND PARTICIPANTS We used data from a pilot r and omized controlled trial in which 644 adults aged 60 to 84 years were r and omly assigned to monthly doses of placebo , 30 000 IU , or 60 000 IU vitamin D3 for 12 months . Baseline characteristics were obtained from a self-administered question naire . Eighty-eight single-nucleotide polymorphisms ( SNPs ) in 41 c and i date genes were genotyped using Sequenom MassArray technology . Serum 25(OH)D levels before and after the intervention were measured using the Diasorin Liaison platform immunoassay . We used linear regression models to examine associations between genetic and nongenetic factors and change in serum 25(OH)D levels . RESULTS Supplement dose and baseline 25(OH)D level explained 24 % of the variability in response to supplementation . Body mass index , self-reported health status , and ambient UV radiation made a small additional contribution . SNPs in CYP2R1 , IRF4 , MC1R , CYP27B1 , VDR , TYRP1 , MCM6 , and HERC2 were associated with change in 25(OH)D level , although only CYP2R1 was significant after adjustment for multiple testing . Models including SNPs explained a similar proportion of variability in response to supplementation as models that included personal and environmental factors . CONCLUSION Stepwise regression analyses suggest that genetic variability may be associated with response to supplementation , perhaps suggesting that some people might need higher doses to reach optimal 25(OH)D levels or that there is variability in the physiologically normal level of Purpose To investigate the association between serum 25-hydroxyvitamin D [ 25(OH)D ] concentration , a marker of vitamin D status , and risk of all-cause and cardiovascular mortality in a general older population with relatively low average serum 25(OH)D concentrations . Methods The study population included 552 men and 584 women aged 53–73 years who were free of CVD and cancer at baseline in 1998–2001 from the prospect i ve , population -based Kuopio Ischaemic Heart Disease Risk Factor ( KIHD ) Study . Deaths were ascertained by a computer linkage to the national cause of death register . All deaths that occurred from the study entry to December 31 , 2008 , were included . Cox proportional hazards regression models were used to analyze the association between serum 25(OH)D and risk of death . Results The mean serum 25(OH)D concentration was 43.7 nmol/L ( SD 17.8 ) , with a strong seasonal variation . During the average follow-up of 9.1 years , 87 participants died , 35 from cardiovascular disease ( CVD ) . After multivariable-adjustments , the hazard ratios ( HR ) for all cause death in the tertiles of serum 25(OH)D were 1 , 1.68 ( 95 % CI : 0.92 , 3.07 ) and 2.06 ( 95 % CI : 1.12 , 3.80 ) , p for trend = 0.02 . Conclusions Our study supports the accumulating evidence from epidemiological studies that vitamin D deficiency is associated with increased risk of death . Large-scale primary prevention trials with vitamin D supplementation are warranted OBJECTIVES To examine the effect of 25-hydroxyvitamin D ( 25(OH)D ) levels recommended by Endocrine Society guidelines ( > 30 ng/mL ) on cognition in healthy older African-American women over 3 years . DESIGN R and omized , double-blind , placebo-controlled clinical trial . SETTING Bone Mineral Research Center at New York University Winthrop Hospital . PARTICIPANTS Healthy postmenopausal African American women aged 65 and older ( N=260 ; mean age 68.2 ± 4.9 ; 46 % college education or higher ) . INTERVENTION Half of the women were r and omized to receive vitamin D ( adjusted to achieve a serum level > 30 ng/mL ) with calcium ( diet and supplement total of 1,200 mg ) , and half were r and omized to receive placebo with calcium ( 1,200 mg ) . MEASUREMENTS Cognitive assessment s every 6 months using the Mini-Mental State Examination ( MMSE ) to detect cognitive decline . Mean MMSE scores were calculated over time for both groups . Those with MMSE scores less than 21 at baseline were excluded . RESULTS The average dose of vitamin D3 was 3,490 ± 1,465 IU per day , and average serum 25(OH)D at 3 years was 46.8 ± 1.2 ng/mL in the active group and 20.7 ± 1.1 ng/mL in the  placebo group . Serum 25(OH)D concentration was maintained at greater than 30 ng/mL in 90 % of the active group . Over the 3-year period , MMSE scores increased in both groups ( p < .001 ) , although change over time was not significantly different between the groups . No adverse events associated with vitamin D were observed . CONCLUSION There was no difference in cognition over time between older African-American women with serum concentrations of 25(OH)D of 30 ng/mL and greater than those taking placebo . There is no evidence to support vitamin D intake greater than the recommended daily allowance in this population for preventing cognitive decline . J Am Geriatr Soc 67:81 - 86 , 2019 Summary The aim of this study was to investigate vitamin D status and stress fracture risk during Royal Marine military training . Poor vitamin D status was associated with an increased risk of stress fracture .  Vitamin D supplementation may help to reduce stress fracture risk in male military recruits with low vitamin D status . Introduction Stress fracture is a common overuse injury in military recruits , including Royal Marine ( RM ) training in the UK . RM training is recognised as one of the most arduous basic training programmes in the world . Associations have been reported between serum 25-hydroxyvitamin D ( 25(OH)D ) and risk of stress fracture , but the threshold of 25(OH)D for this effect remains unclear . We aim ed to determine if serum 25(OH)D concentrations were associated with stress fracture risk during RM training . Methods We prospect ively followed 1082 RM recruits ( males aged 16–32 years ) through the 32-week RM training programme . Troops started training between September and July . Height , body weight and aerobic fitness were assessed at week 1 . Venous blood sample s were drawn at weeks 1 , 15 and 32 . Serum sample s were analysed for 25(OH)D and parathyroid hormone ( PTH ) . Results Seventy-eight recruits ( 7.2 % ) suffered a total of 92 stress fractures . Recruits with a baseline serum 25(OH)D concentration below 50 nmol L−1 had a higher incidence of stress fracture than recruits with 25(OH)D concentration above this threshold ( χ2(1 ) = 3.564 , p = 0.042 ; odds ratio 1.6 ( 95 % confidence interval ( CI ) 1.0–2.6 ) ) . Baseline serum 25(OH)D varied from 47.0 ± 23.7 nmol L−1 in February , to 97.3 ± 24.6 nmol L−1 in July ( overall mean 69.2 ± 29.2 nmol L−1 , n = 1016 ) . There were weak inverse correlations between serum 25(OH)D and PTH concentrations at week 15 ( r = −0.209 , p < 0.001 ) and week 32 ( r = −0.214 , p < 0.001 ) , but not at baseline . Conclusion Baseline serum 25(OH)D concentration below 50 nmol L−1 was associated with an increased risk of stress fracture . Further studies into the effects of vitamin D supplementation on stress fracture risk are certainly warranted Background Symptomatic vitamin D deficiency is associated with slowed growth in children . It is unknown whether vitamin D repletion in children with asymptomatic serum vitamin D deficiency can restore normal growth . Objective We tested the impact of vitamin D-supplementation on serum concentrations of 25-hydroxyvitamin D [ 25(OH)D ] and short-term growth in Mongol children , with very low serum vitamin D levels in winter . Design We conducted two r and omized , double-blind , placebo-controlled trials in urban school age children without clinical signs of rickets . The Supplementation Study was a 6-month intervention with an 800 IU vitamin D3 supplement daily , compared with placebo , in 113 children aged 12–15 years . A second study , the Fortification Study , was a 7-week intervention with 710 ml of whole milk fortified with 300 IU vitamin D3 daily , compared with unfortified milk , in 235 children aged 9–11 years . Results At winter baseline , children had low vitamin D levels , with a mean ( ±SD ) serum 25-hydroxyvitamin D [ 25(OH)D ] concentration of 7.3 ( ±3.9 ) ng/ml in the Supplementation Study and 7.5 ( ±3.8 ) ng/ml in the Fortification Study . The serum levels increased in both vitamin D groups — by 19.8 ( ±5.1 ) ng/ml in the Supplementation Study , and 19.7 ( ±6.1 ) ng/ml in the Fortification Study . Multivariable analysis showed a 0.9 ( ±0.3 SE ) cm greater increase in height in the vitamin-D treated children , compared to placebo treated children , in the 6-month Supplementation Study ( p = 0.003 ) . Although the children in the 7-week Fortification Study intervention arm grew 0.2 ( ±0.1 ) cm more , on average , than placebo children this difference was not statistically significant ( p = 0.2 ) . There were no significant effects of vitamin D supplements on differences in changes in weight or body mass index in either trial . For the Fortification Study , girls gained more weight than boys while taking vitamin D 3 ( p-value for interaction = 0.03 ) , but sex was not an effect modifier of the relationship between vitamin D3 and change in either height or BMI in either trial . Conclusions Correcting vitamin D deficiency in children with very low serum vitamin D levels using 800 IU of vitamin D3 daily for six months increased growth , at least in the short-term , whereas , in a shorter trial of 300 IU of D fortified milk daily for 7 weeks did not BACKGROUND There is increasing interest in the extraskeletal effects of vitamin D , particularly in the obese state with regard to the development of insulin resistance and diabetes . OBJECTIVE The objective of the study was to determine the effect of 2 doses of cholecalciferol ( vitamin D3 ) supplementation on insulin action ( Si ) and pancreatic β-cell function in obese adolescents . METHODS We performed a 12-wk double-blind , r and omized comparison of the effect of vitamin D3 supplementation on Si and β-cell function in obese Caucasian adolescents ( body mass index > 95(th ) percentile ) . The subjects were r and omly assigned to receive either 400 IU/d ( n = 25 ) or 2000 IU/d ( n = 26 ) of vitamin D3 . Each subject underwent a 7- sample 75 g oral glucose tolerance test , with glucose , insulin , and C-peptide measurements , to calculate Si and β-cell function as assessed by the disposition index ( DI ) , with use of the oral minimal model before and after supplementation . A total of 51 subjects aged 15.0 ± 1.9 y were enrolled . Included for analysis at follow-up were a total of 46 subjects ( 20 male and 26 female adolescents ) , 23 in each group .  RESULTS Initial serum 25-hydroxyvitamin D [ 25(OH)D ] was 24.0 ± 8.1 μg/L. There was no correlation between 25(OH)D concentrations and Si or DI . There was a modest but significant increase in 25(OH)D concentration in the 2000 IU/d group ( 3.1 ± 6.5 μg/L , P = 0.04 ) but not in the 400 IU/d group ( P = 0.39 ) . There was no change in Si or DI  following vitamin D3 supplementation in either of the treatment groups ( all P > 0.10 ) . CONCLUSIONS The current study shows no effect from vitamin D3 supplementation , irrespective of its dose , on β-cell function or insulin action in obese nondiabetic adolescents with relatively good vitamin D status . Whether obese adolescents with vitamin D deficiency and impaired glucose metabolism would respond differently to vitamin D3 supplementation remains unclear and warrants further studies . This trial was registered at clinical trials.gov as NCT00858247 Objectives : Vitamin D is critical for skeletal health ; hypovitaminosis D is common in pediatric inflammatory bowel disease ( IBD ) , yet optimal repletion therapy is not well studied . We aim ed to conduct a pilot trial comparing the efficacy of 2 vitamin D regimens of weekly dosing for the repletion of hypovitaminosis D in pediatric IBD . Methods : Subjects identified from our IBD clinic with 25-hydroxyvitamin D ( 25[OH]D ) concentrations < 30 ng/mL were r and omized to 10,000 ( n = 18 ) or 5000 ( n = 14 ) IU of oral vitamin D3/10 kg body weight per week for 6 weeks  . Serum 25(OH)D , Ca , and parathyroid hormone concentrations were measured at baseline , week 8 , and week 12 . Results : In the higher dosing group , serum 25(OH)D increased from 23.7 ± 8.5 ng/mL at baseline to 49.2 ± 13.6 ng/mL at 8 weeks ; P < 0.001 . In the lower dosing group , serum 25(OH)D increased from 24.0 ± 7.0 ng/mL at baseline to 41.5 ± 9.6 ng/mL at 8 weeks ; P < 0.001 . At 12 weeks , serum 25(OH)D concentrations were 35.1 ± 8.4 and 30.8 ± 4.2 ng/mL for the higher and lower dose regimens , respectively . Mean serum Ca and parathyroid hormone concentrations did not significantly change during the study . No patient exhibited hypercalcemia , and no serious adverse events occurred . Conclusions : Both treatment arms were safe and effective at normalizing vitamin D nutriture in pediatric IBD . Although significant repletion of 25(OH)D concentration was achieved in both dosing groups at 8 weeks , this effect was lost by the 12-week follow-up . Maintenance vitamin D therapy following initial repletion is likely required to maintain long-term normalized vitamin D status Background / Objectives : Middle Eastern female immigrants are at an increased risk of vitamin D deficiency and their response to prescribed vitamin D dosages may not be adequate and affected by other factors . The objectives were to determine vitamin D deficiency and its determinants in Middle Eastern women living in Auckl and , New Zeal and ( Part-I ) , and to determine serum 25-hydroxyvitamin D ( serum-25(OH)D ) response to two prescribed vitamin D dosages ( Part-II ) in this population . Participants / Methods : Women aged ⩾20 ( n=43 ) participated in a cross-sectional pilot study during winter ( Part-I ) . In Part-II , women aged 20–50 years ( n=62 ) participated in a r and omised , double-blind placebo-controlled trial consuming monthly either 50 000 , 100 000 IU vitamin D3 or placebo for 6 months ( winter to summer ) . Results : All women in Part-I and 60 % women in Part-II had serum-25(OH)D<50 nmol/l . Serum-25(OH)D was higher in prescribed vitamin D users than nonusers ( P=0.001 ) and in Iranians than Arab women ( P=0.001 ; Part-I ) . Mean ( s.d . ) serum-25(OH)D increased in all groups ( time effect , P<0.001 ) and differed between groups ( time × dosage interaction , P<0.001 ; 50 000 IU : from 44.0±16.0 to 70.0±15.0 nmol/l ; 100 000 IU : 48.0±11.0 to 82.0±17.0 nmol/l ; placebo : 45.0±18.0 to 54.0±18.0 nmol/l ) . Only 32 % and 67 % achieved serum-25(OH)D⩾75 nmol/l with 50 000 and 100 000 IU/month , respectively . Predictors of 6-month change in serum-25(OH)D were dose ( B-coefficient±s.e . ; 14.1±2.4 , P<0.001 ) , baseline serum-25(OH)D ( −0.6±0.1 , P<0.001 ) and body fat percentage ( −0.7±0.3 , P=0.01 ) . Conclusions : Vitamin D deficiency/insufficiency is highly prevalent in this population . Monthly 100 000 IU vitamin D for 6 months is more effective than 50 000 IU in achieving serum-25(OH)D ⩾75 nmol/l ; however , a third of women still did not achieve these levels OBJECTIVE Inconsistent effects of vitamin A supplementation on prevention of  bronchopulmonary dysplasia  have been reported . Meta- analysis of these reports result ed in a relative risk of 0.69 - 1.02 for death or bronchopulmonary dysplasia associated with vitamin A supplementation . Effective dosage regimens or serum retinol concentrations have not been determined in previous reports . The purpose of this pilot study was to define a vitamin A regimen that produces serum retinol concentrations of 25 - 55 micrograms/dl . STUDY DESIGN In this three-phase study , 91 infants ( mean birth weight 799 - 864 g ) were enrolled .  Vitamin A was administered three times/week for 4 weeks at an average daily dose of 986 - 2143 IU/day . Physical examinations were performed and serum retinol specimens were collected weekly to assess clinical signs of toxicity . RESULTS The majority of serum retinol concentrations remained < 25 micrograms/dl until an intramuscular vitamin A dose of 5000 IU/dose three times/week was used . No clinical signs of toxicity were associated with the higher dosage and higher serum concentrations of vitamin A. CONCLUSION A large clinical trial of vitamin A supplementation with 5000 IU/dose three times/week ( 25 - 114 % more than the dose used in the three published clinical trials ) is needed to assess whether vitamin A supplementation  safely reduces the risk of bronchopulmonary dysplasia  in very-low-birth-weight infants Although there have been several studies of the effect of vitamin D status on bone turnover in the elderly , the findings are unclear , and , furthermore , to date very few have investigated this in young adults . The objective of these r and omized , placebo-controlled , double-blind , 2-center intervention studies was to investigate the effect of cholecalciferol supplementation ( 0 , 5 , 10 , and 15 microg cholecalciferol/d ) throughout winter time on indices of vitamin D status and bone turnover in young ( aged 20 - 40 y ; n = 215 ) and elderly ( aged > or = 64 y ; n = 204 ) adults , with relatively high mean calcium intakes of 976 and 874 mg/d , respectively .  Fasting serum concentrations of 25-hydroxyvitamin D [ 25(OH)D ] , parathyroid hormone ( PTH ) , osteocalcin , bone-specific alkaline phosphatase , and carboxyterminal collagen crosslinks were measured by enzyme immunoassays at baseline and endpoint . Fok I and Taq I vitamin D receptor ( VDR ) genotypes were determined by real-time PCR . Endpoint serum 25(OH)D increased ( P < 0.0001 ) in a dose-related manner with increasing supplemental cholecalciferol ( up to 15 microg/d ) in 20 - 40-y olds and up to 10 microg/d in > or = 64-y olds . Endpoint serum PTH was lower ( P < 0.05 ) in the 3 cholecalciferol-supplemented groups compared with that in the placebo group in > or = 64-y olds , but cholecalciferol supplementation did not affect other markers in either cohort and there was no significant interaction with VDR genotype . In conclusion , cholecalciferol supplementation alone throughout winter did not affect bone turnover markers in apparently healthy young and elderly adults , even when stratified by VDR genotype BACKGROUND Low serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations have been associated with insulin resistance , the metabolic syndrome , and type 2 diabetes . Because many non-Western immigrants in the Netherl and s are vitamin D deficient , obese , and at high risk of diabetes , vitamin D supplementation may contribute to prevent diabetes and insulin resistance . OBJECTIVE We examined the effect of vitamin D supplementation on insulin sensitivity and β cell function in overweight , vitamin D-deficient , non-Western immigrants at high risk of diabetes . DESIGN The study was a 16-wk , r and omized , placebo-controlled trial . A total of 130 non-Western immigrants with prediabetes ( fasting glucose concentration > 5.5 mmol/L or r and om glucose concentration from 7.8 to 11.1 mmol/L ) and vitamin D deficiency ( serum 25[OH]D concentration < 50 nmol/L ) were r and omly assigned after stratification by sex to receive either cholecalciferol ( 1200 IU/d ) or a placebo for 16 wk . All participants received 500 mg Ca/d as calcium carbonate . The primary outcome was the difference in the area under the curve of insulin and glucose after a 75-g oral-glucose-tolerance test after 4 mo of treatment . Secondary outcomes were insulin-sensitivity variables , β cell-function variables , and metabolic syndrome . RESULTS Mean serum 25(OH)D concentrations increased significantly in the vitamin D compared with placebo groups . After 4 mo of therapy , the mean between-group difference was 38 nmol/L ( 95 % CI : 32.1 , 43.9 nmol/L ; P < 0.001 ) . There was no significant effect on insulin sensitivity and β cell function . In a post hoc analysis , when patients with diabetes at baseline were excluded , a significant increase in the insulinogenic index was observed in participants who obtained a 25(OH)D concentration ≥60 nmol/L ( P = 0.040 ) . CONCLUSIONS Vitamin D supplementation in non-Western vitamin D-deficient immigrants with prediabetes did not improve insulin sensitivity or β cell function or change the incidence of metabolic syndrome . However , after the exclusion of diabetic subjects , an improvement in the insulinogenic index was observed in participants who obtained a 25(OH)D concentration ≥60 nmol/L. This trial was registered at trialregister.nl as NTR1827 Introduction The purpose of this study was to examine the relationships of vitamin D supplementation and serum concentrations of vitamin D metabolites and parathyroid hormone ( PTH ) with neuromuscular function and falls in older community-dwelling women . Methods We examined these relationships using a 4-year prospect i ve multi-center study among 9,526 community-dwelling women enrolled in the Study of Osteoporotic Fractures ( median age : 70 years ; interquartile range : 67–75 ) and a subset of 389 women ( 97 % ) out of 400 who were r and omly selected from the entire cohort for serum measures . Measurements included :  vitamin D supplementation , serum 25-hydroxyvitamin D3 [ 25(OH)D3 ] , serum 1,25-dihydroxyvitamin D3 [ 1,25(OH ) 2D3 ] , and serum intact parathyroid hormone ( iPTH ) ; grip and quadriceps strength , chair-st and time , walking speed , reaction time , and balance-walk time ( including changes in grip strength , chair-st and time , walking speed and balance-walk time over approximately 3.7 years ) ; and incident fall rates ( number of falls/woman-years ) . Results In 9,526 women , vitamin D supplementation was not associated with any measures of neuromuscular function , change in neuromuscular function , or fall rates ( p>0.01 for all ) . In a subgroup of 389 women , there was a trend of higher 25(OH)D3 concentration with slightly weaker grip strength ( p=0.007 ) , and women in the fourth quartile of 1,25(OH)2D3 had a faster chair-st and time ( p=0.017 ) than women in the first quartile ; still , in general , concentrations of 25(OH)D3 , 1,25(OH)2D3 , and iPTH were not associated with either neuromuscular function or changes in neuromuscular function ( p>0.05 for all ) . However , higher 1,25(OH)2D3 concentration was associated with lower fall rates ( p=0.039 ) . Conclusions Higher 1,25(OH)2D3 concentration is associated with a lower fall risk in older community-dwelling women , but vitamin D supplementation , and 25(OH)D3 and iPTH concentrations are not associated with either neuromuscular function or falls It is now generally accepted that vitamin D deficiency is a worldwide health problem that affects not only musculoskeletal health but also a wide range of acute and chronic diseases . However , there remains cynicism about the lack of r and omized controlled trials to support the association studies regarding the nonskeletal health benefits of vitamin D. This review was obtained by search ing English- language studies published up to April 1 , 2013 , in PubMed , MEDLINE , and the Cochrane Central Register of Controlled Trials ( search terms : vitamin D and supplementation ) and focuses on recent challenges regarding the definition of vitamin D deficiency and how to achieve optimal serum 25-hydroxyvitamin D concentrations from dietary sources , supplements , and sun exposure . The effect of vitamin D on fetal programming epigenetics and gene regulation could potentially explain why vitamin D has been reported to have such wide-ranging health benefits throughout life . There is potentially a great upside to increasing the vitamin D status of children and adults worldwide for improving musculoskeletal health and reducing the risk of chronic illnesses , including some cancers , autoimmune diseases , infectious diseases , type 2 diabetes mellitus , neurocognitive disorders , and mortality Background Although there have been marked improvements in our underst and ing of vitamin D functions in different diseases , gaps on its role during pregnancy remain . Due to the lack of consensus on the most accurate marker of vitamin D deficiency during pregnancy and the optimal level of 25-hydroxyvitamin D , 25(OH)D , for its definition , vitamin D deficiency assessment during pregnancy is a complicated process . Besides , the optimal protocol for treatment of hypovitaminosis D and its effect on maternal and neonatal outcomes are still unclear . Objective The aim of our study was to estimate the prevalence of vitamin D deficiency in the first trimester of pregnancy and to compare vitamin D screening strategy with no screening . Also , we intended to compare the effectiveness of various treatment regimens on maternal and neonatal outcomes in Masjed-Soleyman and Shushtar cities of Khuzestan province , Iran . Methods This was a two-phase study . First , a population -based cross-sectional study was conducted ; recruiting 1600 and 900 first trimester pregnant women from health centers of Masjed-Soleyman and Shushtar , respectively , using stratified multistage cluster sampling with probability proportional to size ( PPS ) method . Second , to assess the effect of screening strategy on maternal and neonatal outcomes , Masjed-Soleyman participants were assigned to a screening program versus Shushtar participants who became the nonscreening arm . Within the framework of the screening regimen , an 8-arm blind r and omized clinical trial was undertaken to compare the effects of various treatment protocol s. A total of 800 pregnant women with vitamin D deficiency were selected using simple r and om sampling from the 1600 individuals of Masjed-Soleyman as interventional groups . Serum concentrations of 25(OH)D were classified as : ( 1 ) severe deficient ( < 10ng/ml ) , ( 2 ) moderate deficient ( 10 - 20ng/ml ) , and ( 3 ) normal status ( > 20ng/ml ) . Those with severe and moderate deficiency were r and omly divided into 4 subgroups and received vitamin D3 based on protocol and were followed until delivery . Data was analyzed according to the intention-to-treat principle . Results Recruitment commenced in July , 2014 , and as estimated , nearly 3.5 years is needed to complete the study . Results of this study will ( 1 ) provide reliable information regarding the prevalence of vitamin D deficiency during pregnancy using universal vitamin D screening approach and ( 2 ) determine the beneficial effects of universal screening and compare the various treatment protocol s in terms of pregnancy outcomes . Conclusions Since vitamin D deficiency is a prevalent disorder in pregnancy among Iranian population , this study will ensure creation of reliable evidence -based findings and will enable clinicians to better evaluate and treat vitamin D deficient pregnant women . Trial Registration International St and ard R and omized Controlled Trial Number ( IS RCT N ) : 2014102519660N1 ; http://www.i rct .ir/ search result .php?keyword=&id=19660&number=1&prt=7805&total=10&m=1 ( Archived by WebCite at http://www.webcitation.org/6p3lkqFdV BACKGROUND Adequate intakes of calcium and vitamin D reduce bone loss and fracture risk in the elderly . Other nutrients also affect bone health , and adequate intakes may influence bone turnover and balance . OBJECTIVE We compared the long-term effects on bone turnover markers and calciotropic hormones of a multinutrient supplement , a calcium and vitamin D supplement , and dietary instruction aim ed at increasing calcium intake through foods . DESIGN Ninety-nine healthy postmenopausal women participated in a 3-y , r and omized trial , receiving either 1 ) supplemental calcium ( 1450 mg/d ) and vitamin D [ 10 microg ( 400 IU)/d ] , 2 ) calcium , vitamin D , and other nutrients ( multinutrient supplement ) , or 3 ) dietary instruction ( dietary control group ) . Data are from 83 subjects who completed the trial . RESULTS Increases over baseline in calcium intakes and serum 25-hydroxyvitamin D concentrations were sustained over 3 y in all treatment groups . Circulating parathyroid hormone concentrations were reduced at year 1 in all treatment groups but trended toward baseline thereafter . Bone turnover markers followed a similar pattern , and none of the changes in biochemical concentrations differed significantly between groups . CONCLUSIONS All 3 interventions offer long-term feasibility for increasing calcium intake and serum 25-hydroxyvitamin D concentrations . The dietary addition of micronutrients implicated in skeletal physiology confers no obvious bone-sparing effect in healthy postmenopausal women beyond that of calcium and vitamin D alone . The attenuation over time in suppression of parathyroid hormone and bone turnover might help explain why nutrient intervention tends to have less of a bone-sparing effect than do skeletally active medications such as estrogen or bisphosphonates CONTEXT Public health authorities around the world recommend widely variable supplementation strategies for adults , whereas several professional organizations , including The Endocrine Society , recommend higher supplementation . METHODS We analyzed published r and omized controlled clinical trials to define the optimal intake or vitamin D status for bone and extraskeletal health . CONCLUSIONS The extraskeletal effects of vitamin D are plausible as based on pre clinical data and observational studies . However , apart from the beneficial effects of 800 IU/d of vitamin D3 for reduction of falls in the elderly , causality remains yet unproven in r and omized controlled trials ( RCTs ) . The greatest risk for cancer , infections , cardiovascular and metabolic diseases is associated with 25-hydroxyvitamin D ( 25OHD ) levels below 20 ng/mL. There is ample evidence from RCTs that calcium and bone homeostasis , estimated from serum 1,25-dihydroxyvitamin D and PTH , calcium absorption , or bone mass , can be normalized by 25OHD levels above 20 ng/mL. Moreover , vitamin D supplementation ( 800 IU/d ) in combination with calcium can reduce fracture incidence by about 20 % . Such a dose will bring serum levels of 25OHD above 20 ng/mL in nearly all postmenopausal women . Based on calculations of the metabolic clearance of 25OHD , a daily intake of 500 - 700 IU of vitamin D3 is sufficient to maintain serum 25OHD levels of 20 ng/mL. Therefore , the recommendations for a daily intake of 1500 - 2000 IU/d or serum 25OHD levels of 30 ng or higher for all adults or elderly subjects , as suggested by The Endocrine Society Task Force , are premature . Fortunately , ongoing RCTs will help to guide us to solve this important public health question CONTEXT Guidelines in Finl and recommend 10 μg of vitamin D3 daily for all infants . Recent observations suggest that this may be insufficient to maintain optimal serum 25-hydroxyvitamin D ( S-25-OHD ) . OBJECTIVE The aim of the study was to evaluate effects of various vitamin D doses and determine a dose ensuring S-25-OHD of at least 80 nmol/liter in infants without signs of vitamin D excess . DESIGN We conducted a r and omized double-blind intervention study . Cord blood was obtained at birth for S-25-OHD ; 113 infants were r and omized to receive vitamin D3 10 , 30 , or 40 μg/d from age 2 wk to 3 months . SETTING An investigator-initiated study was performed in a single maternity hospital in Helsinki , Finl and . MAIN OUTCOME MEASURES S-25-OHD , calcium homeostasis , and skeletal characteristics were evaluated with peripheral quantitative computed tomography at age 3 months . RESULTS Baseline S-25-OHD was similar in all three groups ( median , 53 nmol/liter ) . At 3 months , the mean S-25-OHD values were 88 , 124 , and 153 nmol/liter , and the minimum values were 46 , 57 , and 86 nmol/liter in the groups receiving 10 , 30 , and 40 μg ( ANOVA ; P < 0.001 ) . No hypercalcemia occurred ; plasma calcium , serum PTH , and urine calcium excretion was similar between the groups . Peripheral quantitative computed tomography showed a trend toward larger tibial total bone and cortical bone area with higher vitamin D doses . CONCLUSION Vitamin D3 supplementation with up to 40 μg/d from age 2 wk to 3 months was safe and caused no hypercalcemia or hypercalciuria . The 40-μg dose maintained S-25-OHD above 80 nmol/liter in all infants . More extensive and longer intervention studies are necessary to assess long-term effects BACKGROUND The maximal calcium absorption in response to vitamin D has been proposed as a biomarker for vitamin D sufficiency . OBJECTIVE The objective was to determine whether there is a threshold beyond which increasing doses of vitamin D , or concentrations of serum 25-hydroxyvitamin D [ 25(OH)D ] , no longer increase calcium absorption . DESIGN This was a placebo-controlled , dose-response , r and omized , double-blind study of the effect of vitamin D on calcium absorption in healthy postmenopausal women . Seventy-six healthy postmenopausal women were r and omly assigned to placebo or 800 IU ( 20 μg ) , 2000 IU ( 50 μg ) , or 4000 IU ( 100 μg ) vitamin D₃ for 8 wk . The technique of dual isotopes of stable calcium was used with a calcium carrier to measure calcium absorption at baseline and after 8 wk . RESULTS Seventy-one women with a mean ± SD age of 58.8 ± 4.9 y completed the study . The mean calcium intake was 1142 ± 509 mg/d and serum 25(OH)D was 63 ± 14 nmol/L at baseline . A statistically significant linear trend of an increase in calcium absorption adjusted for age and body mass index with increasing vitamin D₃ dose or serum 25(OH)D concentration was observed . A 6.7 % absolute increase in calcium absorption was found in the highest vitamin D₃ group ( 100 μg ) . No evidence of nonlinearity was observed in the dose-response curve . CONCLUSIONS No evidence of a threshold of calcium absorption was found with a serum 25(OH)D range from 40 to 130 nmol/L. Calcium absorption in this range is not a useful biomarker to determine nutritional recommendations for vitamin Background : Dark skin and low exposure to sunlight increase the risk of vitamin D insufficiency in children . Objective : The aim of the study was to evaluate the amount of vitamin D needed to ascertain that most children > 4 y of age attain sufficient serum 25-hydroxyvitamin D [ S-25(OH)D ; i.e. , ≥50 nmol/L ] during winter regardless of latitude and skin color . Design : In a longitudinal , double-blind , r and omized , food-based intervention study , 5- to 7-y-old children from northern ( 63 ° N ) and southern ( 55 ° N ) Sweden with fair ( n = 108 ) and dark ( n = 98 ) skin were included . Children , stratified by skin color by using Fitzpatrick 's definition , were r and omly assigned to receive milk-based vitamin D3 supplements that provided 2 ( placebo ) , 10 , or 25 μg/d during 3 winter months . Results : Mean daily vitamin D intake increased from 6 to 17 μg and 26 μg in the intervention groups supplemented with 10 and 25 μg , respectively . In the intention-to-treat analysis , 90.2 % ( 95 % CI : 81.1 % , 99.3 % ) of fair-skinned children r and omly assigned to supplementation of 10 μg/d attained sufficient concentrations , whereas 25 μg/d was needed in dark-skinned children to reach sufficiency in 95.1 % ( 95 % CI : 88.5 % , 100 % ) . In children adherent to the study product , 97 % ( 95 % CI : 91.3 % , 100 % ) and 87.9 % ( 95 % CI : 76.8 % , 99 % ) of fair- and dark-skinned children , respectively , achieved sufficient concentrations if supplemented with 10 μg/d . By using 95 % prediction intervals for 30 and 50 nmol S-25(OH)D/L , intakes of 6 and 20 μg/d are required in fair-skinned children , whereas 14 and 28 μg/d are required in children with dark skin . Conclusion : Children with fair and dark skin require vitamin D intakes of 20 and 28 μg/d , respectively , to maintain S-25(OH)D ≥50 nmol/L , whereas intakes of 6 and 14 μg/d , respectively , are required to maintain concentrations ≥30 nmol/L during winter . This trial was registered at clinical trials.gov as NCT01741324 It is hypothesized that vitamin D insufficiency in athletes might negatively affect sport performance . The objective of this study was to examine the effect of vitamin D3 supplementation on physical performance of adolescent swimmers with vitamin D insufficiency . Fifty-three adolescent competitive swimmers with vitamin D insufficiency ( serum 25-hydroxyvitamin-D concentrations ( 25(OH)D ) < 30 ng/ml , mean 24.2 ± 4.8 ng/ml ) were r and omized to receive 2,000 IU/day of vitamin D3 or placebo for 12 weeks . Swimming performance at several speeds , arm-grip strength , and one-legged balance , were measured before and after supplementation . The age-adjusted changes in performance variables during the study were compared between groups . 25(OH ) D concentrations at study end were significantly higher in the vitamin group compared with the placebo group ( 29.6 ± 6.5 ng/ml vs. 20.3 ± 4.2 ng/ml , p < .001 ) , yet only 48 % of the vitamin group became vitamin D sufficient with this dosing . No between-group differences were found in the changes of the performance variables tested . No significant differences in performance were found between participants that became vitamin D sufficient , and those who did not . No significant correlation was found between the change in serum 25(OH)D and age-adjusted balance , strength or swimming performance at study end . Vitamin D3 supplementation that raised serum 25(OH)D concentrations by a mean of 9.3 ng/ml above placebo in adolescent swimmers with vitamin D insufficiency , did not improve physical performance more than placebo Background : During pregnancy , Low serum 25-hydroxyvitamin-D [ 25(OH)D ] concentration is even more critical . This deficiency leads to higher incidences of preeclampsia , gestational diabetes , preterm birth , bacterial vaginosis , and also affects the health of the infants . The aim of this study was to evaluate the relationships between serum levels of 25-hydroxyvitamin D ( 25[OH]D )  and gestational diabetes mellitus ( GDM ) and differences in high-risk pregnant women and women without risk factors for GDM . Methods : This cross sectional study including 155 pregnant women , who are still in the first trimester of pregnancy ( less than 12 weeks gestation ) , were r and omized to two groups of high and low risk for GDM . For these people , once at the gestational age less than 12 times a week and once at for 24 to 28 weeks of pregnancy , tests of FBS / BS / HbA1C / 25OHD / insulin / Ca / Albumin was requested . Besides , the OGTT test was performed with 75 g glucose at 24 and 28 weeks of pregnancy to diagnose GDM . Results : Serum levels of 25(OH)D in the second trimester of pregnancy ng / ml ( 24.1 ± 39.5 ) was significantly lower than that of the first trimester ng / ml ( 25.9 ± 45.6 ) ( p < 0.001 ) . But serum 25(OH)D levels in the first and second trimester of pregnancy was significantly different in women at high risk for GDM than women who had no risk factors ( p = 0.584 and p = 0.99 ) . Serum levels of 25(OH)D has an inverse and significant relationship with HbA1C at the beginning of pregnancy ( p=0.007 ) . In addition , a significant and inverse relationship was shown between serum levels of 25(OH)D in the second trimester with insulin ( p=0.047 ) and blood sugar 2 hours after ingestion of 75 g glucose ( p=0.045 ) at 24 - 28 weeks of gestation . Conclusion : Regarding to the relationship between serum levels of 25(OH)D and blood sugar and insulin at the second trimester of pregnancy , it is recommended for pregnant women to take vitamin D supplementation BACKGROUND Epidemiological evidence supports a relationship between vitamin D and mental well-being , although evidence from large-scale placebo-controlled intervention trials is lacking . AIMS To examine if vitamin D supplementation has a beneficial effect on mood in community-dwelling older women ; if a single annual large dose of vitamin D has a role in the prevention of depressive symptoms ; and if there is an association between serum 25-hydroxyvitamin D levels and mental health . METHOD A double-blind , r and omised , placebo-controlled trial of women aged 70 or older ( the Vital D Study : IS RCT N83409867 and ACTR12605000658617 ) . Participants were r and omly assigned to receive 500 000 IU vitamin D(3 ) ( cholecalciferol ) orally or placebo every autumn/winter for 3 - 5 consecutive years . The tools utilised at various time points were the General Health Question naire , the 12-item Short Form Health Survey , the Patient Global Impression-Improvement scale and the WHO Well-Being Index . Serum 25-hydroxyvitamin D levels were measured in a subset of 102 participants . RESULTS In this non- clinical population , no significant differences between the vitamin D and placebo groups were detected in any of the measured outcomes of mental health . Serum 25-hydroxyvitamin D levels in the vitamin D group were 41 % higher than the placebo group 12 months following their annual dose . Despite this difference , scores from the question naires did not differ . Furthermore , there was no interaction between those on antidepressant/anxiety medication at baseline and the treatment groups . CONCLUSIONS The lack of improvement in indices of mental well-being in the vitamin D group does not support the hypothesis that an annual high dose of vitamin D(3 ) is a practical intervention to prevent depressive symptoms in older community-dwelling women BACKGROUND Skeletal abnormalities have been reported in HIV-infected children and adolescents . Although the etiology is not well understood , vitamin D deficiency may be involved . OBJECTIVE The study objective was to evaluate the effect of vitamin D and calcium supplementation on bone mass accrual in HIV-infected youth . DESIGN Perinatally HIV-infected children were r and omly assigned to receive vitamin D ( 100,000 IU cholecalciferol given every 2 mo ) and calcium ( 1 g/d ) ( supplemented group ) or double placebo ( placebo group ) for 2 y. The total-body bone mineral content ( TB BMC ) , total-body bone mineral density ( TBBMD ) , spine bone mineral content ( S BMC ) , and spine bone mineral density ( SBMD ) were assessed by using dual-energy X-ray absorptiometry at baseline and at 2 annual follow-up visits . RESULTS Fifty-nine participants , aged 6 - 16 y , were r and omly assigned to either the supplemented ( n = 30 ) or the placebo ( n = 29 ) group . At enrollment , supplemented and placebo groups did not differ with respect to age , sex , dietary intakes of vitamin D and calcium , mean baseline serum 25-hydroxyvitamin D [ 25(OH)D ] concentration , TB BMC , TBBMD , S BMC , or SBMD . Significant increases in serum 25(OH)D were observed in the supplemented group but not in the placebo group . TB BMC , TBBMD , S BMC , and SBMD increased significantly at 1 and 2 y in both groups . No between-group differences were observed at any time before or after adjustment for stage of sexual maturation by mixed linear model analysis . CONCLUSION One gram of calcium per day and oral cholecalciferol at a dosage of 100,000 IU every 2 mo administered to HIV-infected children and adolescents did not affect bone mass accrual despite significant increases in serum 25(OH)D concentrations . This trial was registered at clinical trials.gov as NCT00724178 Background It is unclear whether maternal vitamin D supplementation during pregnancy and lactation improves fetal and infant growth in regions where vitamin D deficiency is common . Methods We conducted a r and omized , double‐blind , placebo‐controlled trial in Bangladesh to assess the effects of weekly prenatal vitamin D supplementation ( from 17 to 24 weeks of gestation until birth ) and postpartum vitamin D supplementation on the primary outcome of infants ' length‐for‐age z scores at 1 year according to World Health Organization ( WHO ) child growth st and ards . One group received neither prenatal nor postpartum vitamin D ( placebo group ) . Three groups received prenatal supplementation only , in doses of 4200 IU ( prenatal 4200 group ) , 16,800 IU ( prenatal 16,800 group ) , and 28,000 IU ( prenatal 28,000 group ) . The fifth group received prenatal supplementation as well as 26 weeks of postpartum supplementation in the amount of 28,000 IU ( prenatal and postpartum 28,000 group ) . Results Among 1164 infants assessed at 1 year of age ( 89.5 % of 1300 pregnancies ) , there were no significant differences across groups in the mean ( ±SD ) length‐for‐age z scores . Scores were as follows : placebo , ‐0.93±1.05 ; prenatal 4200 , ‐1.11±1.12 ; prenatal 16,800 , ‐0.97±0.97 ; prenatal 28,000 , ‐1.06±1.07 ; and prenatal and postpartum 28,000 , ‐0.94±1.00 ( P=0.23 for a global test of differences across groups ) . Other anthropometric measures , birth outcomes , and morbidity did not differ significantly across groups . Vitamin D supplementation had expected effects on maternal and infant serum 25‐hydroxyvitamin D and calcium concentrations , maternal urinary calcium excretion , and maternal parathyroid hormone concentrations . There were no significant differences in the frequencies of adverse events across groups , with the exception of a higher rate of possible hypercalciuria among the women receiving the highest dose . Conclusions In a population with widespread prenatal vitamin D deficiency and fetal and infant growth restriction , maternal vitamin D supplementation from midpregnancy until birth or until 6 months post partum did not improve fetal or infant growth . ( Funded by the Bill and Melinda Gates Foundation ; Clinical Trials.gov number , NCT01924013 . Background / Objectives : Vitamin D mediates immunomodulatory functions , and its deficiency has been associated with an increased prevalence of immunological diseases . The supplementation of vitamin D might be therapeutically beneficial , for example , in lupus erythematosus patients . However , its affect on established recall immune responses is undefined . Subjects/ Methods : In all , 32 individuals were r and omized in a placebo controlled , double-blind setting , and received vitamin D ( daily 2000 IU ) for 10 weeks followed by tetanus toxoid ( TT ) booster immunization . Results : During vitamin D supplementation the median 25-hydroxyvitamin D serum concentration increased to 80.3 nM , which as expected decreased in the placebo group to 29.1 nM during the ultraviolet-deprived winter months . The TT-specific immunoglobulin G ( IgG ) boost efficiency was marginal higher in the vitamin D group ( P=0.04 ) . The increase of the 25-hydroxyvitamin D levels correlated with the increase of TT – IgG serum concentrations . The induction of specific serum IgA and specific antibody secreting cells was comparable between both groups . Accordingly , the TT-specific and polyclonally triggered T-cell cytokine profiles were stable as well . Conclusions : Vitamin D supplementation was successful and booster immunization induced efficiently specific antibodies titers BACKGROUND Older adults may be more prone to developing vitamin D deficiency than younger adults . Dietary requirements for vitamin D in older adults are based on limited evidence . OBJECTIVE The objective was to establish the dietary intake of vitamin D required to maintain serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations above various cutoffs between 25 and 80 nmol/L during wintertime , which accounted for the effect of summer sunshine exposure and diet . DESIGN A r and omized , placebo-controlled , double-blind , 22-wk intervention was conducted in men and women aged > /=64 y ( n = 225 ) at supplemental levels of 0 , 5 , 10 , and 15 microg vitamin D(3)/d from October 2007 to March 2008 . RESULTS Clear dose-related increments ( P < 0.0001 ) in serum 25(OH)D were observed with increasing supplemental vitamin D(3 ) intakes . The slope of the relation between total vitamin D intake and serum 25(OH)D was 1.97 nmol . L(-1 ) . microg intake(-1 ) . The vitamin D intake that maintained serum 25(OH)D concentrations > 25 nmol/L in 97.5 % of the sample was 8.6 microg/d . Intakes were 7.9 and 11.4 microg/d in those who reported a minimum of 15 min daily summer sunshine exposure or less , respectively . The intakes required to maintain serum 25(OH)D concentrations of > 37.5 , > 50 , and > 80 nmol/L in 97.5 % of the sample were 17.2 , 24.7 , and 38.7 microg/d , respectively . CONCLUSION To ensure that the vitamin D requirement is met by the vast majority ( > 97.5 % ) of adults aged > /=64 y during winter , between 7.9 and 42.8 microg vitamin D/d is required , depending on summer sun exposure and the threshold of adequacy of 25(OH)D. This trial was registered at http://www.controlled-trials.com/IS RCT N20236112 as IS RCT N registration no. IS RCT N20236112 SETTING Newham Chest Clinic , London , UK . OBJECTIVE To determine the safety and efficacy of the administration of bolus-dose vitamin D(2 ) in elevating serum 25-hydroxyvitamin D ( 25[OH]D ) concentrations in tuberculosis ( TB ) patients . DESIGN A multi-ethnic cohort of TB patients was r and omised to receive a single oral dose of 2.5 mg vitamin D(2 ) ( n = 11 ) or  placebo ( n = 14 ) . Serum 25(OH)D and corrected calcium concentrations were determined at baseline and 1 week and 8 weeks post-dose , and compared to those of a multi-ethnic cohort of 56 healthy adults receiving an identical dose of vitamin D(2 ) . RESULTS Hypovitaminosis D ( serum 25[OH]D < 75 nmol/l ) was present in all patients at baseline . A single oral dose of 2.5 mg vitamin D2 corrected hypovitaminosis D in all patients in the intervention arm of the study at 1 week post-dose , and induced a 109.5 nmol/l mean increase in their serum 25(OH)D concentration . Hypovitaminosis D recurred in 10/11 patients at 8 weeks post-dose . No patient receiving vitamin D(2 ) experienced hypercalcaemia . Patients receiving 2.5 mg vitamin D(2 ) experienced a greater mean increase in serum 25(OH)D at 1 week post-dose than healthy adults receiving 2.5 mg vitamin D(2 ) . CONCLUSION A single oral dose of 2.5 mg vitamin D(2 ) corrects hypovitaminosis D at 1 week but not at 8 weeks post-dose in TB patients Objective : Results from studies examining associations between serum 25-hydroxyvitamin D ( 25(OH)D ) concentrations and depressive symptoms are equivocal . We investigated the relationship between serum 25(OH)D concentrations and symptoms of depression , anxiety and stress in a cross-sectional analysis of a population -based sample of young adults participating in the Western Australian Pregnancy Cohort ( Raine ) Study . Methods : Participants provided a blood sample at the 20-year follow-up ( March 2010-April 2012 ) for the  measurement of serum 25(OH)D concentrations .  Mental health symptoms were assessed using the  21-item Depression Anxiety Stress Scales ( DASS-21 ) . Associations between serum 25(OH)D concentrations and total DASS-21 scores and subscale scores of depression , anxiety and stress were explored in males and females using negative binomial regression , adjusting for age , race , body mass index ( BMI ) and physical activity ( n=735 ) . Models examining subscale scores were also adjusted for the other subscale scores . Results : After adjusting for confounders , an increase in serum 25(OH)D concentrations of 10 nmol/L decreased total DASS-21 scores in males by 9 % ( rate ratio ( RR ) 0.91 ; 95%CI 0.87,0.95 ; p<0.001 ) and depression subscale scores in males by 8 % ( RR 0.92 ; 95%CI 0.87,0.96 ; p=0.001 ) . However , in adjusted models there were no significant associations between serum 25(OH)D concentrations and symptoms of anxiety and stress in males . There were no significant associations between serum 25(OH)D concentrations and symptoms of depression , anxiety and stress in females . Conclusions : We found an association between serum 25(OH)D concentrations and symptoms of depression , but not anxiety and stress , in males . R and omised controlled trials are necessary to determine any benefit of vitamin D supplementation in the prevention and treatment of depressive symptoms in young adults OBJECTIVE To evaluate , in a r and omized fashion , the impact of vitamin D supplementation on CD4 count and measures of vitamin D homeostasis in children infected with human immunodeficiency virus ( HIV ) . STUDY DESIGN Children infected with HIV ( n = 54 ) were r and omized to receive no supplementation ( group 1 ) , vitamin D 5600 IU/week ( group 2 ) , or vitamin D 11 200 IU/week ( group 3 ) for 6 months . Viral load , CD4 percent , CD4 count , 25-hydroxyvitamin D ( 25[OH]D ) , 1,25-dihydroxyvitamin D , and other measures of vitamin D metabolism were measured at baseline and 6 months later . RESULTS A total of 53 participants completed the study . The mean age , CD4 percent , CD4 count , and log(10 ) viral load at baseline were 10.3 ± 3.9 years , 33 % ± 10 % , 927 ± 468 cells/μL , and 1.63 ( 95 % CI , 0.76 - 2.50 ) , respectively . The mean baseline 25(OH)D level was 53.1 ± 24.8 nmol/L ; 85 % of participants were vitamin D insufficient or deficient ( < 75 nmol/L ) . Serum levels of 25(OH)D increased significantly in participants who received supplementation with vitamin D ( P = .0002 and P < .001 for participants receiving 800 IU/day and 1600 IU/day , respectively ) , but not in participants who did not receive supplementation ( P = .27 ) . Participants treated with 1600 IU/day of vitamin D achieved a higher mean increase in 25(OH)D than participants treated with 800 IU/day ( P = .02 ) . However , only 67 % of the group supplemented with higher dose achieved vitamin D sufficiency . Vitamin D supplementation did not lead to an increase in CD4 percent or CD4 count . CONCLUSION In children infected with HIV with relatively preserved immune function  , vitamin D supplementation in doses as high as 1600 IU/day does not impact CD4 count . Vitamin D insufficiency is common in this population , and achieving vitamin D serum levels of > 75 nmol/L may require a daily intake ≥1600 IU OBJECTIVE To study daily intake of calcium , phosphorus and vitamin D , to determine the biochemical findings of rickets and the effect of sunlight exposure and vitamin D supplementation in school girls with hypovitaminosis D. METHODS A cross-sectional study was conducted on school girls aged 11 - 15 years selected r and omly from various areas of Tehran , Iran .  Dietary information and amount of sunlight exposure were estimated by a 7 day recalling method using self-reported question naire . Hypovitaminosis D defined as low serum 25-hydroxyvitamin D concentration with two or more others abnormal biochemical findings . Girls with hypovitaminoses D were r and omly divided into two groups . The faces and h and s of girls in group 1 were exposed to sunlight for one hour per day for twenty days , while those in group 2 were administered vitamin D capsules , 50,000 IU per day for the same period . RESULTS four-hundred fourteen girls evaluated , mean daily calcium intake , sunlight exposure and vitamin D acquirement were 360 mg , 10 minutes and 119 IU , respectively . Mean serum 25-hydroxyvitamin D concentration was 30 ng/ml among all girls whereas in 15 ( 3.63 % ) of 414 girls was 7.8 ng/ml . Abnormal biochemical findings in these girls included hypocalcemia ( n=4 ) , hypophosphatemia ( n=5 ) , raised serum alkaline phosphatase ( n=13 ) , and parathyroid hormone ( n=15 ) . After intervention , mean serum 25-hydroxyvitamin D concentration  in sunlight exposure ( n=8 ) and vitamin D ( n=7 ) supplementation increased to 14.4+/-4 ng/ml and 23+/-4 ng/ml respectively . There was a significant difference between the two groups ( p<0.05 ) . CONCLUSION Vitamin D deficiency developed in rapid growth period of girls without clear clinical rickets in sunny temperate climate city in Iran which vitamin D supplementation improved biochemical findings better than sunlight exposure INTRODUCTION Maternal circulating 25-hydroxyvitamin D [ 25(OH)D ] has been shown to optimize production of 1,25-dihydroxyvitamin D [ 1,25(OH)2D ] during pregnancy at approximately 100nmoles/L , which has pronounced effects on fetal health outcomes . Additionally , associations are noted between low maternal 25(OH)D concentrations and vascular pregnancy complications , such as preeclampsia . To further eluci date the effects of vitamin D activity in pregnancy , we investigated the role of maternal 25(OH)D , the nutritional indicator of vitamin D status , in relation to placental maintenance and , specifically , expression of placental gene targets related to angiogenesis and vitamin D metabolism . METHODS A focused analysis of placental mRNA expression related to angiogenesis , pregnancy maintenance , and vitamin D metabolism was conducted in placentas from 43 subjects enrolled in a r and omized controlled trial supplementing 400IU or 4400IU of vitamin D3 per day during pregnancy . Placental mRNA was isolated from biopsies within one hour of delivery , followed by quantitative PCR . We classified pregnant women with circulating concentrations of < 100nmoles/L as deficient and those with ≥100nmoles/L as sufficient . The value of each gene 's change in the PCR cycle threshold ( ΔCT ) , which is a relative measure of target concentration , was compared with maternal 25(OH)D concentrations < 100nmoles/L and ≥100nmoles/L based on a two- sample Wilcoxon test . RESULTS Soluble FMS-like tyrosine kinase 1 ( sFlt-1 ) and vascular endothelial growth factor ( VEGF ) gene expression was significantly downregulated in the maternal subgroup with circulating 25(OH)D ≥100ng/mL compared to the subgroup < 100ng/mL. DISCUSSION Here , we report a significant association between maternal vitamin D status and the expression of sFlt-1 and VEGF at the mRNA level . Achieving maternal circulating 25(OH)D ≥100nmoles/L suggests the impact of maternal vitamin D3 supplementation on gene transcription in the placenta , thereby potentially decreasing antiangiogenic factors that may contribute to vascular pregnancy complications OBJECTIVE The purpose of this study was to determine 1,25-dihydroxyvitamin D3 [ 1,25(OH)2D3 ] and 1,25-dihydroxyvitamin D2 [ 1,25(OH)2D2 ] levels in healthy adults consuming 1000 IU vitamin D2 or vitamin D3 per day for 11 weeks . SUBJECTS AND DESIGN Blood from 34 healthy male and female adults , aged 18 to 79 years , from a placebo-controlled , double-blind study who received a placebo , 1000 IU vitamin D3 , or 1000 IU vitamin D2 daily for 11 weeks at end of winter was analyzed . Serum levels of 25-hydroxyvitamin D2 , 25-hydroxyvitamin D3 , 1,25(OH)2D2 , and 1,25(OH)2D3  were determined by liquid chromatography-t and em mass spectroscopy . RESULTS Of the adults , 82 % were vitamin D insufficient ( serum 25-hydroxyvitamin D [ 25(OH)D < 30 ng/mL ] ) at the start of the study . Administration of vitamin D2 and vitamin D3 induced similar increases in total 25(OH)D as well as in 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3 , respectively . Compared with placebo and adjusting for baseline levels , 1000 IU daily of vitamin D2 was associated with a mean increase of 7.4 pg/mL ( 95 % confidence interval , 4.4 - 10.3 ) in 1,25(OH)2D2 , which was accompanied by a mean decrease of 9.9 pg/mL ( -15.8 to -4.0 ) in 1,25(OH)2D3 . No such differences accompanied administration of 1000 IU daily of vitamin D3 . CONCLUSION Vitamin D2 and vitamin D3 were effective in raising and maintaining total serum concentrations of 25(OH)D. Ingestion of vitamin D2 also result ed in an increase in serum concentrations of 1,25(OH)2D2 . This increase was accompanied by a comparable decrease in serum concentrations of 1,25(OH)2D3 ; therefore , the total 1,25-dihydroxyvitamin D [ 1,25(OH)2D ] concentrations did not significantly change after 11 weeks compared with baseline levels . Ingestion of vitamin D3 did not alter serum concentrations of 1,25(OH)2D3 or total 1,25(OH)2D . Therefore , ingestion of 1000 IU vitamin D2 or vitamin D3 for 11 weeks was effective in raising total serum concentrations of 25(OH)D as well as sustaining serum concentrations of total 1,25(OH)2D OBJECTIVE Improve vitamin D status in lactating women and their recipient infants , and measure breast milk calcium concentration [ Ca ] as a function of vitamin D regimen . DESIGN / METHODS Fully breastfeeding mothers were r and omized at 1 month postpartum to 2000 ( n = 12 ) or 4000 ( n = 13 ) IU/day vitamin D for 3 months to achieve optimal vitamin D status [ serum 25(OH)D > or = 32 ng/mL ( 80 nmol/L ) ] . Breast milk [ Ca ] , maternal and infant serum 25(OH)D and serum Ca , and maternal urinary Ca/Cr ratio were measured monthly . RESULTS Mothers were similar between groups for age , race , gestation , and birth weight . 25(OH)D increased from 1 to 4 months in both groups ( mean + /- SD ) : + 11.5 + /- 2.3 ng/mL for group 2000 ( p = 0.002 ) and + 14.4 + /- 3.0 ng/mL for group 4000 ( p = 0.0008 ) . The 4000 IU/day regimen was more effective in raising both maternal and infant serum levels and breast milk antirachitic activity than the 2000 IU/day regimen . Breast milk [ Ca ] fell with continued lactation through 4 months in the 2000 and 4000 IU groups . Decline in breast milk [ Ca ] was not associated with vitamin D dose ( p = 0.73 ) or maternal 25(OH)D ( p = 0.94 ) . No mother or infant experienced vitamin D-related adverse events , and all laboratory parameters remained in the normal range . CONCLUSION High-dose vitamin D was effective in increasing 25(OH)D levels in fully breastfeeding mothers to optimal levels without evidence of toxicity . Breast milk [ Ca ] and its decline in both groups during 1 to 4 months were independent of maternal vitamin D status and regimen . Both the mother and her infant attained improved vitamin D status and maintained normal [ Ca ] BACKGROUND Vitamin D has been added to calcium-fortified orange juice . It is unknown whether vitamin D is as bioavailable from orange juice as it is from supplements . OBJECTIVES The objective was to compare the bioavailability of vitamin D(2 ) and vitamin D(3 ) from orange juice with that from vitamin D(2 ) and vitamin D(3 ) supplements . A secondary aim was to determine which form of vitamin D is more bioavailable in orange juice . DESIGN A r and omized , placebo-controlled , double-blind study was conducted in healthy adults aged 18 - 84 y ( 15 - 20/group ) who received 1000 IU vitamin D(3 ) , 1000 IU vitamin D(2 ) , or placebo in orange juice or capsule for 11 wk at the end of winter . RESULTS A total of 64 % of subjects began the study deficient in vitamin D ( ie , 25-hydroxyvitamin D [ 25(OH)D ] ) concentrations < 20 ng/mL ) . Analysis of the area under the curve showed no significant difference in serum 25(OH)D between subjects who consumed vitamin D-fortified orange juice and those who consumed vitamin D supplements ( P = 0.084 ) . No significant difference in serum 25(OH)D(3 ) was observed between subjects who consumed vitamin D(3)-fortified orange juice and vitamin D(3 ) capsules ( P > 0.1 ) . Similarly , no significant difference in serum 25(OH)D(2 ) was observed between subjects who consumed vitamin D(2)-fortified orange juice and vitamin D(2 ) capsules ( P > 0.1 ) . No significant overall difference in parathyroid hormone concentrations was observed between the groups ( P = 0.82 ) . CONCLUSION Vitamin D(2 ) and vitamin D(3 ) are equally bioavailable in orange juice and capsules Background : The Institute of Medicine ( IOM ) dietary guidelines for vitamin D are based on limited pediatric data . Our objective was to estimate the dietary vitamin D requirements for maintaining serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations at the various IOM-considered thresholds of vitamin D status ( 12 , 16 , and 20 ng/ml ) during fall and winter in children . Methods : Ninety-six healthy 8- to 14-y-old Pittsburgh-area black and white children enrolled in a r and omized , placebo-controlled trial of vitamin D3 1,000 IU daily for 6 mo with baseline and 2-mo follow-up assessment s completed during October through April were studied .  Vitamin D intake from diet and study supplement adjusted for adherence and serum 25(OH)D were measured . Results : The  vitamin D intakes needed to maintain serum 25(OH)D concentrations at 12 , 16 , and 20 ng/ml in 90 % of the children were 581 , 1,062 , and 1543 IU/day , respectively . The estimated  vitamin D intakes needed to maintain serum 25(OH)D concentrations at 20 ng/ml in 97.5 % of the children was 2,098 IU/day . Conclusion : Our data suggest that the current vitamin D recommended dietary allowance ( RDA ) ( 600 IU/day ) is insufficient to cover the skeletal health needs of at least 50 % of black and white children In this double blind , unicentre , r and omized , placebo controlled study , we evaluated the changes in 25-hydroxyvitamin D ( 25(OH)D ) serum levels in 150 young Belgian adults ( 18–30 years ) , monthly supplemented with 50,000 IU of vitamin D ( VTD ) or placebo for 6 months , from November 2010 to May 2011 . At T0 , 30 % of the population presented 25(OH)D serum levels below 20 ng/mL. In the VTD-treated group , mean serum levels increased from 21.2 ± 8.2 to 30.6 ± 8.8 ng/mL ( P < 0.001 ) at T3mo and to 36.0 ± 9.2 ng/mL ( P < 0.001 ) at T6mo . Despite documented VTD intake , no changes in serum levels were , however , observed in 10 % of the treated group . In the placebo group , mean 25(OH)D serum levels decreased from 22.8 ± 8.5 to 14.0 ± 6.9 ng/mL at T3mo ( P < 0.001 ) but returned to values not significantly different from those observed at T0 ( 23.5 ± 8.6 ng/mL ) at T6mo . No difference between serum calcium levels was observed between the groups throughout the study . In conclusion , monthly supplementation with 50,000 UI of VTD in winter can warrant serum 25(OH)D levels above 20 ng/mL in 96.2 % of those healthy young adults without inducing unacceptably high 25(OH)D concentration . This supplementation is safe and may be proposed without 25(OH)D testing PURPOSE Vitamin D deficiency and cardiometabolic risk factors are common in obese adolescents . Observational studies demonstrate an inverse relationship among serum 25-hydroxyvitamin D ( 25OHD ) and obesity , insulin resistance , and inflammatory cytokines . This pilot study explores if vitamin D supplementation could reduce serum concentrations of inflammatory cytokines ( interleukin [ IL ] 6 , IL-10 , tumor necrosis factor α ) , adiponectin , lipids , hemoglobin A1C , and high-sensitivity C-reactive protein ( hs-CRP ) . A secondary aim was to determine the associations between baseline serum 25OHD concentrations and body mass index ( BMI ) , hs-CRP , inflammatory cytokines , and lipids . METHODS Overweight and obese adolescents enrolled in this 24-week , r and omized , double-blind study were given 150,000 IU ergocalciferol or placebo at baseline and 12 weeks . Outcome measurements included serum 25OHD , inflammatory cytokines , adiponectin , hs-CRP , lipids , hemoglobin A1C , and BMI at baseline , 12 , and 24 weeks . RESULTS Of 40 participants , 31 ( 78 % ) completed the study . Mean ± st and ard error 25OHD levels were similar in vitamin D and placebo groups at baseline ( 19.6 ± 5.3 vs. 25.8 ± 10.8 ng/mL ) and 24 weeks ( 20.1 ± 3.4 vs. 24.6 ± 8.4 ng/mL ) . Inflammatory and cardiovascular markers were not significantly different between groups at 24 weeks . Serum 25OHD at baseline was associated with BMI ( r = -.44 [ 95 % confidence interval , -.66 to -.15 ] ) but not with other outcome measures . CONCLUSIONS Supplementation with vitamin D at 150,000 IU every 3 months failed to increase serum 25OHD or alter inflammatory markers and lipids in overweight and obese youth . Further studies are needed to establish the dose of vitamin D required to increase 25OHD and determine potential effects on metabolic risk factors in obese teens BACKGROUND Epidemiological studies suggest a higher prevalence of metabolic syndrome and its components among individuals with vitamin D deficiency . The aim of the present study was to determine whether vitamin D treatment  improves glucose control and insulin sensitivity in Type 2 diabetes mellitus ( T2DM ) . METHODS Subjects with T2DM and serum 25-hydroxyvitamin D ( 25(OH)D ) concentrations < 25 ng/mL were r and omized to receive 400 IU ( Group 1 ) or 1200 IU ( Group 2 ) cholecalciferol for 4 months . Fasting plasma glucose , glycosylated hemoglobin ( HbA1c ) , Quantitative Insulin Sensitivity Check Index ( QUICKI ) , serum lipid levels and serum adiponectin were measured at baseline and at 4 months . RESULTS Mean 25(OH)D levels increased in both groups ( from 17.6±1.5 to 25.5±1.8 ng/mL in Group 1 and from 15.6±1.4 to 27.4±2.4 ng/mL in Group 2 ; P≤0.001 vs baseline for each group ) . No significant differences were noted in fasting plasma glucose , HbA1c , QUICKI , serum adiponectin , and lipid levels compared with baseline within groups or between the two groups . CONCLUSIONS In the present pilot study , conventional vitamin D treatment at a level improving , but not optimizing , serum 25(OH)D did not improve glycemia , insulin sensitivity , or lipid profile . However , diabetes and lipids were relatively well controlled at baseline . Future studies should be design ed to achieve optimal concentrations of serum 25(OH)D ( at least > 32 ng/mL ) and should include subjects showing more abnormal parameters of glycemia , lipid , and insulin sensitivity at baseline Context : Single-nucleotide polymorphisms ( SNPs ) in genes related to vitamin D metabolism have been associated with serum 25-hydroxyvitamin D [ 25(OH)D ] concentration , but these relationships have not been examined following antenatal cholecalciferol supplementation . Objective : To determine whether SNPs in DHCR7 , CYP2R1 , CYP24A1 , and GC are associated with the response to gestational cholecalciferol supplementation . Design : Within-r and omization group analysis of the Maternal Vitamin D Osteoporosis Study trial of antenatal cholecalciferol supplementation . Setting : Hospital antenatal clinics . Participants : In total , 682 women of white ethnicity ( 351 placebo , 331 cholecalciferol ) were included . SNPs at rs12785878 ( DHCR7 ) , rs10741657 ( CYP2R1 ) , rs6013897 ( CYP24A1 ) , and rs2282679 ( GC ) were genotyped . Interventions : 1000 IU/d cholecalciferol from 14 weeks of gestation until delivery . Main Outcome Measure : 25(OH)D at r and omization and 34 weeks of gestation were measured in a single batch ( Liaison ; Diasorin , Dartford , UK ) . Associations between 25(OH)D and the SNPs were assessed by linear regression using an additive model [ β represents the change in 25(OH)D per additional common allele ] . Results : Only rs12785878 ( DHCR7 ) was associated with baseline 25(OH)D [ β = 3.1 nmol/L ; 95 % confidence interval ( CI ) , 1.0 to 5.2 nmol/L ; P < 0.004 ] . In contrast , rs10741657 ( CYP2R1 ) ( β = −5.2 nmol/L ; 95 % CI , −8.2 to −2.2 nmol/L ; P = 0.001 ) and rs2282679 ( GC ) ( β = 4.2 nmol/L ; 95 % CI , 0.9 to 7.5 nmol/L ; P = 0.01 ) were associated with achieved 25(OH)D status following supplementation , whereas rs12785878 and rs6013897 ( CYP24A1 ) were not . Conclusions : Genetic variation in DHCR7 , which encodes 7-dehyrocholesterol reductase in the epidermal vitamin D bio synthesis pathway , appears to modify baseline 25(OH)D. In contrast , the response to antenatal cholecalciferol supplementation was associated with SNPs in CYP2R1 , which may alter 25-hydroxylase activity , and GC , which may affect vitamin D binding protein synthesis or metabolite affinity BACKGROUND Suboptimal vitamin D status is associated with endothelial dysfunction and an increased risk of cardiovascular diseases but it is unclear whether vitamin D supplementation is beneficial . The aim was to investigate the effect of vitamin D supplementation on endothelial function in patients with type 2 diabetes mellitus ( DM ) . METHODS In a double-blind , placebo-controlled trial , we r and omized 100 type 2 DM patients to vitamin D supplement  ( 5000 IU/day , n = 50 ) or placebo ( controls , n = 50 ) for 12 weeks . Assessment of vascular function with brachial artery flow-mediated dilatation ( FMD ) , circulating levels of endothelial progenitor cells ( EPCs ) and brachial-ankle pulse wave velocity , and metabolic parameter , high-sensitivity C-reactive protein ( hsCRP ) and oxidative stress markers were performed before and after the supplementation . RESULTS After 12 weeks , vitamin D treated patients had significant increases in serum 25-hydroxyvitamin D [ 25(OH)D ] concentration ( treatment effect 34.7 ng/mL , 95 % CI 26.4 - 42.9 , P < 0.001 ) and serum ionized calcium ( treatment effect 0.037 mmol/L , 95 % CI 0.007 - 0.067 , P = 0.018 ) ; decreased serum parathyroid hormone concentration ( treatment effect -0.55 pmol/L , 95 % CI -1.08 to -0.02 , P = 0.042 ) compared to patients who received placebo . Nevertheless , vitamin D supplementation did not improve vascular function as determined by FMD , circulating EPC count or baPWV ( all P > 0.05 ) . Furthermore , hsCRP , oxidative stress markers , low- and high-density lipoprotein and glycated hemoglobin were also similar between two groups ( all P > 0.05 ) . CONCLUSION In patients with type 2 DM , 12 weeks oral supplementation of vitamin D did not significantly affect vascular function or serum biomarkers of inflammation and oxidative stress . CLINICAL TRIAL NUMBER HKCTR-867 , www.hk clinical trials.com Background Low serum 25-hydroxyvitamin D [ 25(OH)D ] levels have been associated with higher risk of many diseases that affect mortality , including cardiovascular disease ( CVD ) and cancer . The inverse association between serum 25(OH)D and mortality may be modified by excess circulating vitamin A , due to interactions of vitamin A at the level of the vitamin D nuclear receptor . In this prospect i ve cohort study , we investigated whether the association of 25(OH)D with all-cause , cancer , and CVD mortality  was modified by circulating vitamin A or preformed vitamin A intake from supplements . Methods We analyzed 15,998 adults in the Third National Health and Nutrition Examination Survey ( NHANES III ) , 1988–1994 . Mortality data for all-cause ( n = 3890 ) , cancer ( n = 844 ) , and CVD mortality ( n = 1715 ) were assessed through December 2006 .  Serum 25(OH)D was measured using a radioimmunoassay kit , vitamin A biomarkers were measured by HPLC , and information on supplement use was obtained by self-report . Multivariable hazard ratios ( HRs ) and corresponding 95 % confidence intervals ( CI ) were estimated by proportional hazards regression . Results Serum 25(OH)D was significantly inversely associated with all-cause mortality ( HR 0.93 , 95 % CI 0.89 , 0.97 , per 10 ng/mL increase ) and also with CVD mortality and mortality due to non-cancer/non-cardiovascular causes , but not with cancer mortality . The observed inverse associations remained statistically significant only among participants with serum retinyl esters < 7.0 μg/dL. High intake ( > 5000 IU/day ) of preformed vitamin A from supplements attenuated the inverse association of 25(OH)D with overall mortality . The observed interactions were not statistically significant . Conclusions 25(OH)D was inversely associated with overall mortality , CVD mortality , and mortality due to non-cancer/non-CVD causes , but not with cancer mortality . A possible interaction between vitamin A exposure and 25(OH)D concentration appears to be associated with an attenuation of the inverse association between risk of death and quartile of 25(OH)D concentration Aim / Background : Vitamin D supplementation during pregnancy is a well-accepted recommendation worldwide ; however , the debate about the correct dose is ongoing . We aim ed to compare daily doses of 600 , 1,200 , and 2,000 IU in this r and omized , controlled study . Methods : The study group consisted of 91 pregnant women aged 16 - 42 years admitted to Kocaeli Maternity and Children Hospital between April 2011 and April 2012 . The participants were r and omly divided into 3 groups . 600 , 1,200 , and 2,000 IU/day of vitamin D was supplemented to group 1 ( control group , n = 31 ) , group 2 ( n = 31 ) , and group 3 ( n = 32 ) , respectively . Serum calcium , 25-hydroxyvitamin D ( 25OHD ) , and the calcium/creatinine ratio in spot urine sample s were measured in the follow-up period . The serum calcium and 25OHD levels of the mothers ' infants were measured as well . Results : The frequency of vitamin D sufficiency after supplementation was 80 % in group 3 and it was significantly higher than in groups 1 ( 42 % ) and 2 ( 39 % ) ( p = 0.03 ) . The frequency of vitamin D sufficiency in the infants of the participants was 91 % in group 3 and it was significantly higher than in groups 1 ( 36 % ) and 2 ( 52 % ) ( p = 0.006 ) . Conclusions : At least 2,000 IU/day of vitamin D is needed to ensure adequate vitamin D status in pregnancy and early infancy AIMS To compare depressive symptoms in participants with low and high serum 25-hydroxyvitamin D ( 25(OH)D ) levels and to examine whether supplementation with vitamin D(3 ) would improve symptoms in those with low serum 25(OH)D levels . METHOD Participants with low 25(OH)D levels were r and omised to either placebo or 40 000 IU vitamin D(3 ) per week for 6 months . Individuals with high serum 25(OH)D levels were used as nested controls . Depressive symptoms were evaluated with the Beck Depression Inventory , Hospital Anxiety and Depression Scale , Seasonal Pattern Assessment Scale and Montgomery-Åsberg Depression Rating Scale . The study was registered at Clinical Trials.gov ( NCT00960232 ) . RESULTS Participants with low 25(OH)D levels ( n = 230 ) at baseline were more depressed ( P<0.05 ) than participants with high 25(OH)D levels ( n = 114 ) . In the intervention study no significant effect of high-dose vitamin D was found on depressive symptom scores when compared with placebo . CONCLUSIONS Low levels of serum 25(OH)D are associated with depressive symptoms , but no effect was found with vitamin D supplementation Vitamin D plays an important role in human health . Current recommendations for vitamin D intake and endogenous supply through sun exposure are not met in German pre-school children , and suboptimal serum 25-hydroxyvitamin D concentrations , especially during the winter months , are common . Consequently , vitamin D supplementation or fortification have gained increased acceptance . The KiMi trial ( Kindermilch = growing up milk ) was a prospect i ve , r and omized , and double-blind study in which young children ( 2–6 years of age , n = 92 ) were assigned to receive either vitamin D-fortified growing up milk ( 2.85 μg/100 ml ) or semi skimmed cow 's milk without added vitamin D. Daily consumption of fortified growing up milk contributed to the prevention of an otherwise frequently observed decrease in serum 25-hydroxyvitamin D concentration during winter ( before winter : median 21.5 ng/mL ( 10.1–43.0 ng/mL ) intervention vs. median 18.4 ng/mL ( 11.0–44.9 ng/mL ) control ; after winter : median 24.8 ng/mL ( 7.0–48.2 ng/mL ) intervention vs. median 13.6 ng/mL ( 7.0–36.8 ng/mL ) control ) and proved to be safe during summer ( median 27.6 ng/mL ( 18.8–40.5 ng/mL ) intervention vs. median 27.4 ng/mL ( 17.8–38.7 ng/mL ) control ) . Due to the high prevalence of vitamin D deficiency , fortification of growing up milk with vitamin D at a level used in this study could be an effective measure to improve vitamin D status BACKGROUND The Food and Nutrition Board of the National Academy of Sciences states that 95 microg vitamin D/d is the lowest observed adverse effect level ( LOAEL ) . OBJECTIVE Our objective was to assess the efficacy and safety of prolonged vitamin D3 intakes of 25 and 100 microg ( 1000 and 4000 IU)/d . Efficacy was based on the lowest serum 25-hydroxyvitamin D [ 25(OH)D ] concentration achieved by subjects taking vitamin D3 ; potential toxicity was monitored by measuring serum calcium concentrations and by calculating urinary calcium-creatinine ratios . DESIGN Healthy men and women ( n = 61 ) aged 41 + /- 9 y ( mean + /- SD ) were r and omly assigned to receive either 25 or 100 microg vitamin D3/d for 2 - 5 mo , starting between January and February . Serum 25(OH)D was measured by radioimmunoassay . RESULTS Baseline serum 25(OH)D was 40.7 + /- 15.4 nmol/L ( mean + /- SD ) . From 3 mo on , serum 25(OH)D plateaued at 68.7 + /- 16.9 nmol/L in the 25-microg/d group and at 96.4 + /- 14.6 nmol/L in the 100-microg/d group . Summertime serum 25(OH)D concentrations in 25 comparable subjects not taking vitamin D3 were 46.7 + /- 17.8 nmol/L. The minimum and maximum plateau serum 25(OH)D concentrations in subjects taking 25 and 100 microg vitamin D3/d were 40 and 100 nmol/L and 69 and 125 nmol/L , respectively . Serum calcium and urinary calcium excretion did not change significantly at either dosage during the study . CONCLUSIONS The 100-microg/d dosage of vitamin D3 effectively increased 25(OH)D to high-normal concentrations in practically all adults and serum 25(OH)D remained within the physiologic range ; therefore , we consider 100 microg vitamin D3/d to be a safe intake Objectives : To investigate the practicality and tolerability of high‐dose intramuscular ( i.m . ) vitamin D2 or oral vitamin D3 replacement in vitamin D‐insufficient patients , and to evaluate the biochemical efficacy of each formulation . Methods : Sixty‐nine patients with vitamin D insufficiency [ 25‐hydroxyvitamin D ( 25(OH)D ) < 40 nmol/L ] were recruited from the Rheumatology Outpatient Department of St George 's Hospital , London . In study 1 , 50 patients received 300 000 IU i.m . vitamin D2 ( ergocalciferol ) . In study 2 , 19 patients received 300 000 IU oral vitamin D3 ( cholecalciferol ) under observation . Biochemical response was measured at baseline , and at 12 and 24 weeks . Results : Bolus i.m . vitamin D2 or oral vitamin D3 was well tolerated . The change from baseline in serum 25(OH)D was significantly greater at 6 and 12 weeks in study 2 ( p<0.0001 and < 0.0001 , respectively ) . In study 1 , a modest increase in mean serum 25(OH)D at 6 , 12 , and 24 weeks was observed but no patients achieved a serum 25(OH)D concentration ⩾50 nmol/L. PTH remained elevated in 42 % of patients with secondary hyperparathyroidism at 12 weeks . In study 2 , 100 % and 89 % of patients had serum 25(OH)D>50 nmol/L at 6 and 12 weeks , respectively . All patients with elevated baseline PTH were fully suppressed at 12 weeks . No cases of hypercalcaemia were observed in either group . Conclusion : The 300 000‐IU bolus of vitamin D2 or D3 was practical , well tolerated , and safe . Vitamin D3 had greater potency than equimolar vitamin D2 , with a higher , sustained serum 25(OH)D response and efficacious PTH suppression . To adequately treat vitamin D insufficiency we would recommend administering 300 000 IU oral vitamin D3 approximately three times per year
Overall , intervention groups obtained higher 25(OH)D concentration than controls and there was obvious dose – response effect between intake dose and 25(OH)D concentration .
Baseline 25(OH)D concentration and age were significant indicators for 25(OH)D concentration .
Conclusions Regional- and age-specific recommended dosages of VitD supplements for population to achieve optimal 25(OH)D concentrations have been suggested
Background / Objectives Optimal doses of vitamin D ( VitD ) supplement in different population s are unclear .
We aim to evaluate the relationship between VitD supplementation and post-intervention serum 25-hydroxyvitamin D [ 25(OH)D ] concentration , to provide a recommended dosage of VitD for achieving an optimal 25(OH)D concentration for different population s .