Mandatory fortification of bread with iodised salt modestly improves iodine status in schoolchildren. The Danish investigation on iodine intake and thyroid disease, DanThyr: status and perspectives. Iodine status as determined by urinary iodine excretion in Lesotho two years after introducing legislation on universal salt iodization. Dual fortification of salt with iodine and micronized ferric pyrophosphate: a randomized, double-blind, controlled trial. The impact of iodine supplementation and bread fortification on urinary iodine concentrations in a mildly iodine deficient population of pregnant women in South Australia A multimicronutrient-fortified seasoning powder enhances the hemoglobin, zinc, and iodine status of primary school children in North East Thailand: a randomized controlled trial of efficacy. Dual fortification of salt with iodine and iron: a randomized, double-blind, controlled trial of micronized ferric pyrophosphate and encapsulated ferrous fumarate in southern India. Multi-micronutrient-fortified biscuits decreased prevalence of anemia and improved micronutrient status and effectiveness of deworming in rural Vietnamese school children. The nutritional iodine supply of Belgian neonates is still insufficient Efficacy of daily and weekly multiple micronutrient food-like tablets for the correction of iodine deficiency in Indonesian males aged 6-12 mo. Improved iodine status is associated with improved mental performance of schoolchildren in Benin. Daily Consumption of Lipid-Based Nutrient Supplements Containing 250 μg Iodine Does Not Increase Urinary Iodine Concentrations in Pregnant and Postpartum Women in Bangladesh. Breast-milk iodine concentration declines over the first 6 mo postpartum in iodine-deficient women. Iodine status and thyroid function of pregnant, lactating women and infants (0-1 yr) residing in areas with an effective Universal Salt Iodization program. Triple fortification of salt with microcapsules of iodine, iron, and vitamin A. Serum thyroglobulin and urinary iodine concentration are the most appropriate indicators of iodine status and thyroid function under conditions of increasing iodine supply in schoolchildren in Benin. Selenium and iodine supplementation: effect on thyroid function of older New Zealanders.
Iodine deficiency has re-emerged in many parts of the world including the UK , Australia and New Zeal and ( NZ ) . In 2009 , the NZ government introduced the m and atory fortification of bread with iodised salt as a strategy to improve iodine intakes . The aim of the present study was to assess the impact of fortification on the iodine status of NZ schoolchildren . A school-based cluster survey was used to r and omly select schools from two NZ cities . Children aged 8 - 10 years were administered a general question naire , and asked to provide a casual urine and finger-prick blood sample . The median urinary iodine concentration ( UIC ) of the children ( n 147 ) was 113 μg/l , which falls between 100 and 199 μg/l indicating adequate iodine status ; 12 % of children had a UIC < 50 μg/l and 39 % had a UIC < 100 μg/l . The median serum thyroxine concentration was 115 nmol/l . The median serum thyroglobulin ( Tg ) concentration was 10.8 μg/l and falls in the 10.0 - 19.9 μg/l range indicative of mild iodine deficiency , suggesting that these children still had enlarged thyroid gl and s. When compared with the median UIC of 68 μg/l reported in the 2002 NZ Children 's Nutrition Survey , the UIC of children in the present study had increased , which is probably caused by the addition of iodised salt to bread . However , the elevated concentration of Tg in these children suggests that the increase in UIC is not sufficient to ensure that thyroid volume has normalised . The fortification of other staple foods , in addition to bread , should be considered to ensure good iodine status in NZ children OBJECTIVE Denmark was an area of iodine deficiency , and m and atory iodine fortification of table salt and salt in bread ( 13 p.p.m . iodine ) was initiated in 2000/2001 . The Danish investigation on iodine intake and thyroid disease ( DanThyr ) is the monitoring of the iodine fortification program . DESIGN AND METHODS DanThyr consists of three main parts : a study of population cohorts initialized before ( n=4649 ) and after ( n=3570 ) iodization of salt  , a prospect i ve identification of incident cases of overt hyper- and hypothyroidism in a population of around 550,000 people since 1997 , and compilation of data from the national registers on the use of thyroid medication , thyroid surgery , and radioiodine therapy . Studies were carried-out in parallel in subcohorts living in areas with differences in iodine content of ground water . RESULTS The study showed profound effects of even small differences in iodine intake level on the prevalence of goiter , nodules , and thyroid dysfunction . Mild and moderate iodine deficiency was associated with a decrease in serum TSH with age . Other environmental factors were also important for goiter development ( increase in risk , smoking and pregnancy ; decrease in risk , oral contraception and alcohol consumption ) , and the individual risk depended on the genetic background . Environmental factors had only a minor influence on the prevalence of thyroid autoantibodies in the population . There were more cases of overt hypothyroidism in mild than in moderate iodine deficiency caused by a 53 % higher incidence of spontaneous ( presumably autoimmune ) hypothyroidism . On the other h and , there were 49 % more cases of overt hyperthyroidism in the area with moderate iodine deficiency . The cautious iodine fortification program , aim ing at an average increase in iodine intake of 50 mug/day has been associated with a 50 % increase in incidence of hyperthyroidism in the area with the most severe iodine deficiency . The incidence is expected to decrease in the future , but there may be more cases of Graves ' hyperthyroidism in young people . CONCLUSION A number of environmental factors influence the epidemiology of thyroid disorders , and even relatively small abnormalities and differences in the level of iodine intake of a population have profound effects on the occurrence of thyroid abnormalities . Monitoring and adjustment of iodine intake in the population is an important part of preventive medicine OBJECTIVE Mild to severe iodine deficiency has been documented in Lesotho since 1960 . To eliminate the persisting iodine deficiency , legislation on universal salt iodization was introduced in 2000 as a long-term public health intervention strategy . We assessed the urinary iodine status of school children and women of child-bearing age in Lesotho 2 y after the introduction of legislation on universal salt iodization . METHODS A 31-cluster national survey was conducted in 2002 by using the proportion to population size method . In each cluster , 30 women ages 15 to 30 y and 30 primary school children ages 8 to 12 y were r and omly selected to provide urine sample s for urinary iodine analysis . Data were interpreted according to criteria of the World Health Organization , United Nations Children 's Fund , and International Council for Control of Iodine Deficiency Disorders ( 2001 ) . Statistical analysis was performed using SAS . RESULTS We analyzed 912 urine sample s from children and 924 from women . The median urinary iodine concentrations were 214.7 microg/L for children and 280.1 microg/L for women , indicating more than adequate iodine intake . Median iodine concentration was higher in the lowl and s ( 256.0 microg/L in children and 329.9 microg/L in women ) than in the mountains ( 99.30 microg/L in children and 182.6 microg/L in women ) . Analysis of the distribution of the data showed values below 50 microg/L in 10.1 % of children and in 9.8 % of women . In addition , 21.5 % of children and 17.9 % of women had urinary iodine excretion values below 100 microg/L. In contrast , 36 % of children and 47.2 % of women had urinary iodine concentrations in excess of 300 microg/L. CONCLUSION Results of urinary iodine excretion measurements indicated that iodine deficiency has been eliminated as a public health problem in Lesotho . However , the high median urinary iodine concentration of women in the lowl and s indicated the possibility of a risk of iodine-induced hyperthyroidism in vulnerable people BACKGROUND In many developing countries , children are at high risk for both goiter and anemia . In areas of subsistence farming in rural Africa , salt is one of the few regularly purchased food items and could be a good fortification vehicle for iodine and iron , provided that a stable yet bioavailable iron fortificant is used . OBJECTIVE We tested the efficacy of salt dual-fortified with iodine and micronized ferric pyrophosphate for reducing the prevalence of iodine and iron deficiencies in children . DESIGN In rural northern Morocco , we fortified local salt with 25 microg I ( as potassium io date ) /g salt and 2 mg Fe ( as micronized ferric pyrophosphate ; mean particle size = 2.5 microm)/g salt . After storage and acceptability trials , we compared the efficacy of the dual-fortified salt ( DFS ) with that of iodized salt in a 10-mo , r and omized , double-blind trial in iodine-deficient 6 - 15-y-old children ( n = 158 ) with a high prevalence of anemia . RESULTS After storage for 6 mo , there were no significant differences in iodine content or color lightness between the DFS and iodized salt . During the efficacy trial , the DFS provided approximately 18 mg Fe/d ; iron absorption was estimated to be approximately 2 % . After 10 mo of treatment in the DFS group , mean hemoglobin increased by 16 g/L ( P < 0.01 ) , iron status and body iron stores increased significantly ( P < 0.01 ) , and the prevalence of iron deficiency anemia decreased from 30 % at baseline to 5 % ( P < 0.001 ) . In both groups , urinary iodine ( P < 0.001 ) and thyroid volume ( P < 0.01 ) improved significantly from baseline . CONCLUSION A DFS containing iodine and micronized ferric pyrophosphate can be an effective fortification strategy in rural Africa Mild iodine deficiency during pregnancy can have significant effects on fetal development and future cognitive function . The purpose of this study was to characterise the iodine status of South Australian women during pregnancy and relate it to the use of iodine-containing multivitamins . The impact of fortification of bread with iodized salt was also assessed . Women ( n = 196 ) were recruited prospect ively at the beginning of pregnancy and urine collected at 12 , 18 , 30 , 36 weeks gestation and 6 months postpartum . The use of a multivitamin supplement was recorded at each visit . Spot urinary iodine concentrations ( UIC ) were assessed . Median UICs were within the mildly deficient range in women not taking supplements ( < 90 μg/L ) . Among the women taking iodine-containing multivitamins  UICs were within WHO recommendations ( 150–249 μg/L ) for sufficiency and showed an increasing trend through gestation . The fortification of bread with iodized salt  increased the median UIC from 68 μg/L to 84 μg/L ( p = .011 ) which was still in the deficient range . Pregnant women in this region of Australia were unlikely to reach recommended iodine levels without an iodine supplement , even after the m and atory iodine supplementation of bread was instituted in October 2009 Anemia and co-existing deficiencies of zinc , iron , iodine , and vitamin A occur among children in many developing countries including NE Thail and , probably contributing to impairments in growth , immune competence , and cognition . Sustainable strategies are urgently required to combat these deficiencies . We assessed the efficacy of a micronutrient-fortified seasoning powder served with a school lunch on reducing anemia and improving the micronutrient status of rural NE Thai children . Children ( n = 569 ) aged 5.5 - 13.4y from 10 schools were r and omly assigned to receive a seasoning powder either unfortified or fortified with zinc ( 5 mg ) , iron ( 5 mg ) , vitamin A ( 270 microg ) , and iodine ( 50 microg ) ( per serving ) and incorporated into a school lunch prepared central ly and delivered 5 d/wk for 31 wk . Teachers monitored school lunch consumption . Baseline and final micronutrient status , hemoglobinopathies , and infection or inflammation were assessed from blood and urine sample s. For the primary outcome , anemia ( based on hemoglobin ) , no intervention effect was apparent ( odds ratio : 1.02 95 % CI : 0.69 , 1.51 ) after adjustment for design strata . The odds of zinc ( based on serum zinc ) and urinary iodine deficiency in the fortified group were 0.63 ( 0.42 , 0.94 ) and 0.52 ( 0.38 , 0.71 ) times those in the unfortified group , respectively . Fortification had no effect on serum retinol ( 0.61 : 0.25,1.51 ) , ferritin ( 1.12 : 0.43 , 2.96 ) , or mean red cell volume ( 1.16 : 0.82 , 1.64 ) . Therefore , a micronutrient-fortified seasoning powder is a promising vehicle for improving zinc , iodine , and hemoglobin status , and its potential for incorporation into lunch programs in day care centers and schools in NE Thail and warrants investigation BACKGROUND Dual fortification of salt with iodine and iron could be a sustainable approach to combating iodine and iron deficiencies . OBJECTIVE We compared the efficacy of dual-fortified salt ( DFS ) made by using 2 proposed contrasting formulas-one fortifying with iron as micronized ground ferric pyrophosphate ( MGFePP ) and the other with iron as encapsulated ferrous fumarate (EFF)-with the efficacy of iodized salt ( IS ) in schoolchildren in rural southern India . DESIGN After stability and acceptability testing , a double-blind , household-based intervention was conducted in 5 - 15-y-old children ( n = 458 ) r and omly assigned into 3 groups to receive IS or DFS with iron as MGFePP or EFF , both at 2 mg/g salt . We measured hemoglobin , iron status , and urinary iodine at baseline , 5 mo , and 10 mo . RESULTS Median serum ferritin and calculated median body iron improved significantly in the 2 groups receiving iron . After 10 mo , the prevalence of anemia decreased from 16.8 % to 7.7 % in the MGFePP group ( P < 0.05 ) and from 15.1 % to 5.0 % in the EFF group ( P < 0.01 ) . The median urinary iodine concentration increased significantly in the IS and EFF groups ( P < 0.001 ) but not in the MGFePP group . Losses of iodine in salt with 1.8 % moisture were high for MGFePP , whereas the EFF segregated in salt with 0.5 % moisture and caused color changes in some local foods . CONCLUSIONS Both DFSs were efficacious in reducing the prevalence of anemia and iron deficiency in school-age children . Local salt characteristics should be taken into consideration when choosing an iron fortificant for DFS to achieve optimal iodine stability and color Concurrent micronutrient deficiencies are prevalent among Vietnamese school children . A school-based program providing food fortified with multiple micronutrients could be a cost-effective and sustainable strategy to improve health and cognitive function of  school children . However , the efficacy of such an intervention may be compromised by the high prevalence of parasitic infestation . To evaluate the efficacy of school-based intervention using multi-micronutrient-fortified biscuits with or without deworming on anemia and micronutrient status in Vietnamese schoolchildren , a r and omized , double-blind , placebo-controlled trial was conducted among 510 primary schoolchildren , aged 6 - 8 y , in rural Vietnam .  Albendazole ( Alb ) ( 400 mg ) or placebo was given at baseline . Nonfortified or multi-micronutrient-fortified biscuits including iron ( 6 mg ) , zinc ( 5.6 mg ) , iodine ( 35 microg ) , and vitamin A ( 300 microg retinol equivalents ) were given 5 d/wk for 4 mo . Multi-micronutrient fortification significantly improved the concentrations of hemoglobin ( + 1.87 g/L ; 95 % CI : 0.78 , 2.96 ) , plasma ferritin ( + 7.5 microg/L ; 95 % CI : 2.8 , 12.6 ) , body iron ( + 0.56 mg/kg body weight ; 95 % CI : 0.29 , 0.84 ) , plasma zinc ( + 0.61 micromol/L ; 95 % CI : 0.26 , 0.95 ) , plasma retinol ( + 0.041 micromol/L ; 95 % CI : 0.001 , 0.08 ) , and urinary iodine ( + 22.49 micromol/L ; 95 % CI : 7.68 , 37.31 ) . Fortification reduced the risk of anemia and deficiencies of zinc and iodine by > 40 % . Parasitic infestation did not affect fortification efficacy , whereas fortification significantly enhanced deworming efficacy , with the lowest reinfection rates in children receiving both micronutrients and Alb . Multi-micronutrient fortification of biscuits is an effective strategy to improve the micronutrient status of Vietnamese schoolchildren and enhances effectiveness of deworming Abstract . Belgium used to be affected by mild iodine deficiency . Improvement in iodine nutrition has been recently documented in schoolchildren in Belgium in spite of the absence of any systematic programme of iodine supplementation . The question arises as to whether this ' silent iodine prophylaxis ' affected also the neonates . A total of 185 r and om urine sample s were collected from 90 full term and 65 preterm neonates in Brussels on day 5 and repeated on day 30 in 30 preterms who were bottle-fed with iodine-enriched formula-milk . The iodine content was also determined in 58 sample s of breast-milk on day 5 . The median urinary iodine on day 5 in full term neonates was 86 µg/l , which is markedly higher than the figure of 48 µg/L reported 15 years previously in neonates in the same area but still much lower than normal for this age group ( 150–200 µg/l ) . The mean iodine content of breast-milk was 78 µg/l , which is unchanged as compared to 15 years ago and is about 66 % of normal . Finally , the median urinary iodine increased from 60 µg/l on day 5 to 150 µg/l on day 30 in preterms bottle-fed with iodine-enriched formula-milk . Conclusion : the status of iodine nutrition has also improved spontaneously in Belgian neonates but has not yet normalised . Lactating and probably pregnant women remain clearly iodine deficient . The iodine-enriched formula-milk for preterms is efficient in correcting their iodine deficiency . National measures are urgently required for correction of iodine deficiency in Belgium BACKGROUND Infants are highly vulnerable to iodine deficiency , and little data exist on the effect of multiple micronutrient supplementation on their iodine status . OBJECTIVE We aim ed to compare the efficacy of daily and weekly multiple micronutrient food-like tablets ( foodLETs ) on increasing iodine status among infants . DESIGN In a double-blind , placebo-controlled trial , 133 Indonesian males aged 6 - 12 mo were r and omly assigned to 1 of 4 groups : a daily multiple-micronutrient foodLET providing the Recommended Nutrient Intake (RNI)(DMM ) , a weekly multiple-micronutrient foodLET providing twice the RNI ( WMM ) , a daily 10-mg Fe foodLET ( DI ) , or placebo .  Urinary iodine ( UI ) concentrations were measured at baseline and at 23 wk . RESULTS At baseline , the average UI concentration ( 1.37 micromol/L ) was within the normal range , and 30.8 % of subjects had iodine deficiency ( UI < 0.79 micromol/L ) . At 23 wk , the DMM group had the highest increment in UI ; however , after adjustment for initial UI , the changes in UI were not significantly different between the 4 groups ( P = 0.39 ) . Initial UI correlated inversely with the changes in UI ( P < 0.001 ) . The DMM group had the greatest reduction and increment in the proportion of iodine-deficient infants and in infants with iodine excess , respectively ; however , no significant difference was found in these proportions ( P = 0.13 and P = 0.42 ) between the 4 groups . CONCLUSION Daily consumption of a multiple-micronutrient foodLET providing the RNI during infancy may be one strategy to improve iodine status BACKGROUND An adequate iodine supply in utero and shortly after birth is known to be crucial to an individual 's physical and mental development . The question of whether iodine supplementation later in life can exert a favorable influence on the mental performance of iodine-deficient population s was addressed in various studies , but with contradictory results . OBJECTIVE The aim of this study was to examine the effect of an improvement in iodine status on mental and psychomotor performance of schoolchildren ( 7 - 11 y ) who were moderately to severely iodine deficient . DESIGN The study , which was originally planned as a double-blind , r and omized , placebo-controlled intervention , was carried out in an iodine-deficient population of schoolchildren ( n = 196 ) in northern Benin . As the population began to have access to iodized salt during the 1-y intervention period , the study population was split post hoc-on the basis of urinary iodine concentrations-into a group with improved iodine status and a group with unchanged iodine status . Changes in mental and psychomotor performance over the intervention period were compared . RESULTS Children with increased urinary iodine concentrations had a significantly greater increase in performance on the combination of mental tests than did the group with no change in urinary iodine concentrations . CONCLUSIONS An improvement in iodine status , rather than iodine status itself , determined mental performance in this population , which was initially iodine deficient . These findings suggest a " catch-up " effect in terms of mental performance Background : Maternal iodine deficiency during pregnancy and lactation is common in Bangladesh . Objective : We evaluated the effect of lipid-based nutrient supplements for pregnant and lactating women ( LNS-PL ) on urinary iodine concentration ( UIC ) . Methods : We conducted a cluster-r and omized controlled effectiveness trial in which we enrolled 4011 pregnant women at ≤20 gestational weeks . Women in 48 clusters received iron and folic acid ( IFA ; 60 mg Fe/d + 400 μg folic acid/d ) and women in 16 clusters received LNS-PL ( 20 g/d , 118 kcal ) containing 22 vitamins and minerals ( including 250 μg I ) . We r and omly selected a sub sample of 1159 women for repeated urine sample collection , i.e. , at enrollment , at 36 wk of gestation , and at 6 mo postpartum , for UIC analysis , a secondary outcome of the trial . Results : The geometric mean UIC at 36 wk of gestation and at 6 mo postpartum did not differ significantly between the IFA and LNS-PL groups . The median ( quartile 1 , quartile 3 ) UIC at 36 wk was 27.4 μg/L ( 16.9 , 52.7 μg/L ) in the IFA group and 30.2 μg/L ( 17.7 , 56.6 μg/L ) in the LNS-PL group ; at 6 mo , these were 23.0 μg/L ( 10.0 , 45.9 μg/L ) in the IFA group and 22.2 μg/L ( 9.1 , 50.4 μg/L ) in the LNS-PL group . Conclusion : Daily consumption of LNS-PL containing 250 μg I did not increase the UICs of pregnant and lactating women in Bangladesh . Iodine from lipid-based nutrient supplements may have been stored in the thyroid gl and or secreted in breast milk instead of being excreted in urine . Additional research that uses other biomarkers of iodine status is needed to determine how to meet the iodine requirements of pregnant and lactating women in Bangladesh and similar setting s. This trial was registered at clinical trials.gov as NCT01715038 BACKGROUND Little is known about the iodine status of lactating mothers and their infants during the first 6 mo postpartum or , if deficient , the amount of supplemental iodine required to improve status . OBJECTIVE The objective was to determine maternal and infant iodine status and the breast-milk iodine concentration ( BMI C ) over the first 6 mo of breastfeeding . DESIGN A r and omized , double-blind , placebo-controlled supplementation trial was conducted in lactating women who received placebo ( n = 56 ) , 75 μg I/d ( n = 27 ) , or 150 μg I/d ( n = 26 ) after their infants ' birth until 24 wk postpartum .  Maternal and infant urine sample s and breast-milk sample s were collected at 1 , 2 , 4 , 8 , 12 , 16 , 20 , and 24 wk . Maternal serum thyrotropin and free thyroxine concentrations were measured at 24 wk . RESULTS Over 24 wk , the median urinary iodine concentration ( UIC ) of unsupplemented women and their infants ranged from 20 to 41 μg/L and 34 to 49 μg/L , respectively , which indicated iodine deficiency ( ie , UIC < 100 μg/L ) . Mean maternal UIC was 2.1 - 2.4 times higher in supplemented than in unsupplemented women ( P < 0.001 ) but did not differ significantly between the 2 supplemented groups . BMI C in the placebo group decreased by 40 % over 24 wk ( P < 0.001 ) and was 1.3 times and 1.7 times higher in women supplemented with 75 μg I/d ( P = 0.030 ) and 150 μg I/d ( P < 0.001 ) , respectively , than in unsupplemented women . Thyrotropin and free thyroxine did not differ significantly between groups . CONCLUSION BMI C decreased in the first 6 mo in these iodine-deficient lactating women ; supplementation with 75 or 150 μg I/d increased the BMI C but was insufficient to ensure adequate iodine status in women or their infants . The study was registered with the Australian New Zeal and Clinical Trials Registry as ACTRN12605000345684 OBJECTIVE To assess the iodine nutrition and thyroid function of pregnant women , lactating women and infants residing in areas where the Universal Salt Iodization program is in place . METHODS Pregnant women , lactating women and infants were selected r and omly in the regions where iodized salt coverage rate is more than 90 % since 2000 .  Urine iodine levels of pregnant woman , lactating woman and infants , milk iodine of lactating woman , thyroid-stimulating hormone ( TSH ) and free T4 of women were tested respectively . RESULTS Median Urinary Iodine ( MUI ) of infants , three groups of pregnant women ( first , second and third trimester ) and two groups lactating women ( breastfeeding less than or more than six months ) were 233 , 174 , 180 , 147 , 126 and 145 microg/L , respectively . Median milk iodine of lactating women was 163 microg/L. Percentage of milk iodine < 150 microg/L of early lactating women was 40 % less than that of late lactating women ( p < 0.01).There was a positive correlation between urine iodine of infants and milk iodine of lactating women ( r = 0.526 , p = 0.000 ) . T4 of two women were above or below the reference range . Total 15.4 % women 's TSH were abnormal . Most of these women 's urinary iodine were lower than 150 microg/L. CONCLUSION Iodine status of most of the target population for Universal Salt Iodization program is adequate , but iodine deficiency still existed in some . To assure every new life 's brain not be damaged by iodine deficiency , iodine status of targeted population s should be monitored and supplements provided according to the monitoring outcomes BACKGROUND In many developing countries , children are at high risk of goiter , vitamin A deficiency , and iron deficiency anemia . OBJECTIVE We aim ed to develop a stable , efficacious salt fortified with iodine , iron , and vitamin A. DESIGN A novel spray-cooling technique was used with hydrogenated palm oil to package potassium io date , micronized ferric pyrophosphate , and retinyl palmitate into microcapsules ( mean particle size : 100 mum ) . We used the microcapsules to create triple-fortified salt ( TFS ) with 30 mug I , 2 mg Fe , and 60 mug vitamin A/g salt . After storage trials , we compared the efficacy of TFS with that of iodized salt in a 10-mo , r and omized , double-blind trial in goitrous schoolchildren ( n = 157 ) who had a high prevalence of vitamin A deficiency and iron deficiency anemia . RESULTS After storage for 6 mo , losses of iodine and vitamin A from the TFS were approximately 12 - 15 % , and color was stable . In the TFS group , mean hemoglobin increased by 15 g/L at 10 mo ( P < 0.01 ) , iron status indexes and body iron stores improved significantly ( P < 0.05 ) , and mean serum retinol , retinol-binding protein , and the ratio of retinol-binding protein to prealbumin increased significantly ( P < 0.01 ) . At 10 mo , prevalences of vitamin A deficiency and iron deficiency anemia were significantly lower in the TFS group than in the iodized salt group ( P < 0.001 ) . CONCLUSION Newly developed microcapsules containing iodine , iron , and vitamin A are highly stable when added to local African salt . TFS was efficacious in reducing the prevalence of iron , iodine , and vitamin A deficiencies in school-age children Iodine deficiency control programs have greatly reduced iodine deficiency disorders worldwide . For monitoring changes in iodine status , different indicators may be used . The aim of this study was to evaluate the suitability of indicators of iodine status and thyroid function , thyroglobulin ( Tg ) , thyroid-stimulating hormone ( TSH ) and free thyroxine ( FT4 ) in serum , thyroid volume and urinary iodine concentration , in iodine-deficient schoolchildren under conditions of increasing iodine supply . The study was established as a double-blind , placebo-controlled oral administration of a single dose of iodized oil to schoolchildren ( 7 - 10 y old ) , living in an iodine-deficient area of Benin , with an observation period of 10 mo . However , 3 - 4 mo after supplementation , iodized salt became available in the area . The study population therefore comprised an iodized oil-supplemented group  and a nonsupplemented group  , both of which had variable , uncontrolled intakes of iodized salt during the last 6 mo of the study . Initial mean serum concentrations of TSH and FT4 were within the normal range , whereas serum Tg concentration , urinary iodine concentration and thyroid volume were indicative of moderate-to-severe iodine deficiency . At the end of the study , all indicators had improved significantly , except thyroid volume , which had decreased only in the supplemented group . The supplemented group also still had significantly lower serum Tg and higher urinary iodine concentrations than the nonsupplemented group . Serum Tg and urinary iodine concentrations are the indicators most influenced by a changing iodine supply . Current normal reference ranges of serum concentrations of TSH and FT4 are too wide for detecting iodine deficiency in this age group BACKGROUND The New Zeal and population has both marginal selenium status and mild iodine deficiency . Adequate intakes of iodine and selenium are required for optimal thyroid function . OBJECTIVE The aim of the study was to determine whether low selenium and iodine status compromises thyroid function in an older New Zeal and population . DESIGN We investigated the effects of selenium and iodine supplementation in a double-blind , r and omized , placebo-controlled trial in 100 Dunedin volunteers aged 60 - 80 y. Participants received 100 microg Se/d as l-selenomethionine , 80 microg I , 100 microg Se + 80 microg I , or placebo for 3 mo . Thyroid-stimulating hormone ( TSH ) , free triiodothyronine ( T(3 ) ) , free thyroxine ( T(4 ) ) , thyroglobulin , plasma selenium , whole-blood glutathione peroxidase ( GPx ) activity , and urinary iodine concentrations ( UICs ) were measured . RESULTS Plasma selenium ( P < 0.0001 ) and whole-blood GPx activity ( P<0.0001 ) increased from baseline to week 12 in the selenium and selenium plus iodine groups in comparison with the placebo group . Median UIC at baseline was 48 microg/L ( interquartile range : 31 - 79 microg/L ) , which is indicative of moderate iodine deficiency . UIC increased in the iodine and selenium plus iodine groups and was significant only for the iodine group ( P = 0.0014 ) . Thyroglobulin concentration decreased by 24 % and 13 % of baseline in the iodine and selenium plus iodine groups in comparison with the placebo group ( P = 0.009 and P = 0.108 , respectively ) . No significant treatment effects were found for TSH , free T(3 ) , free T(4 ) , or ratio of T(3 ) to T(4 ) . CONCLUSIONS Additional selenium improved GPx activity but not the thyroid hormone status of older New Zeal and ers . Iodine supplementation alleviated the moderate iodine deficiency and reduced elevated thyroglobulin concentrations . No synergistic action of selenium and iodine was observed . The trial was registered at www.anzctr.org.au/registry/ as ACTRN012605000368639
Despite the high risk of bias of many of the included studies , the results suggested that urinary iodine , thyroglobin , serum thyroxine , and thyroid-stimulating hormone are useful biomarkers of iodine status , at least in some groups .
BACKGROUND Biomarkers of iodine status are required to study iodine deficiency disorders in different parts of the world and to evaluate the effects of fortification strategies .
OBJECTIVE The objective was to assess the usefulness of biomarkers of iodine status in humans by systematic ally review ing intervention studies that altered iodine status .