Study design and sample characteristics
diarrhea, ALL, CHF, overweight, congestive heart failure, diabetes, liver failure, colic
OBESE, RENAL FAILURE, ADVERSE EFFECTS, CHF, BLOOD, HYPERTENSION
This is a randomized, double-blind, placebo-controlled intervention study in which participants were recruited at the Blood Center of the municipality of João Pessoa - Paraíba (PB) - Brazil from March to December 2018. They were invited and then signed the Informed Consent Form (TCLE). The project was submitted to the Research Ethics Committee of the Health Sciences Center (CCS) of the Federal University of Paraíba (UFPB), approved under CAAE number 64573917.4.0000.5188, and registered in the Brazilian Registry of Clinical Trials under number TRIAL: RBR-2PH4F9.Sample calculation was carried out based on the effect of the fiber found on pressure values in a pilot study. The study adopted 95% reliability (Z α/2 = 1.96), a β error of 20% [with power of 80%] (Z β = 0.84). Subsequently, the standard deviation of this distribution was estimated; a fiber effect difference of 12 mmHg was considered and n of at least 11 women per group was found. Participants were randomly distributed into two groups based on medical diagnosis regarding blood pressure values, exclusion criteria (hypertension, diabetes, liver failure, congestive heart failure (CHF), and renal failure), and type of intervention.The initial number of participants was 30. However, there was a sample loss due to inclusion criteria (n = 4) and withdrawal stemming from the occurrence of adverse effects as a result of the use of fiber (colic and diarrhea n = 2). This resulted in a final tally of 11 participants in group one (G1) and 13 participants in group two (G2).This study consisted of 24 overweight and obese normotensive women aged 20–50 years, with those in G1 using mixed dietary fiber (12 g/day) and G2 using placebo (cornstarch, 12 g/day). The intervention period lasted eight weeks for both groups.The mixed dietary fiber was composed of soluble (7 g) and insoluble (5 g) fibers. Soluble fibers were composed of Gum Guar (4g; lot ALL 0605354), Nutraflora (FOS; 1g; lot Galena (CIQ): 1505006204), Psyllium (2g; scientific name Plantago ovata; manufacturer batch: 949/2013) and insoluble fibers (5g; Microcrystalline Cellulose 101–5g, batch 14116094A, manufacturing batch C1404014, formula C6nH10n + 205n = 1). Mixed dietary fiber and placebo were manufactured at a third-party pharmacy.Regarding inclusion criteria, they were overweight and obese normotensive women with systolic blood pressure (SBP) ≤ 130 mmHg and diastolic blood pressure (DBP) ≤ 80 mmHg, age between 20 and 50 years, and a body mass index (BMI) above 25 up to 35 kilograms per square meter (Kg/mThe selected women who agreed to participate in the intervention study intended to kept their eating habits and level of physical activity stable for four weeks before the start of the intervention and communicated that they did not intend to change them throughout the study.