TitleInfluence of Vitamin D Supplementation on Growth, Body Composition, and Pubertal Development Among School-aged Children in an Area With a High Prevalence of Vitamin D Deficiency: A Randomized Clinical Trial.
Publication TypeJournal Article
Year of Publication2023
AuthorsGanmaa D, Bromage S, Khudyakov P, Erdenenbaatar S, Delgererekh B, Martineau AR
JournalJAMA Pediatr
Date Published2023 Jan 01
KeywordsBody Composition, Child, Cholecalciferol, Dietary Supplements, Double-Blind Method, Female, Humans, Male, Prevalence, Vitamin D, Vitamin D Deficiency, Vitamins

IMPORTANCE: Vitamin D deficiency (defined as 25-hydroxyvitamin D [25(OH)D] <20 ng/mL) is prevalent among children living in temperate climates and has been reported to associate independently with stunting, obesity, and early activation of the hypothalamic-pituitary-gonadal axis. Phase 3 randomized clinical trials to investigate the influence of long-term vitamin D replacement on growth, body composition, and pubertal development of school-aged children with vitamin D deficiency are lacking.

OBJECTIVE: To determine whether weekly oral vitamin D supplementation influences linear growth, body composition, or pubertal development in school-aged children living in a setting where vitamin D deficiency is highly prevalent.

DESIGN, SETTING, AND PARTICIPANTS: This secondary analysis of a double-blind, placebo-controlled randomized clinical trial was conducted from June 2016 to June 2019 at 18 grade schools in Ulaanbaatar, Mongolia. School-aged children (6 to 13 years at baseline) attending participating schools were included. Exclusion criteria included a positive QuantiFERON-TB Gold in-tube assay result, conditions or medications associated with altered vitamin D metabolism, use of vitamin D supplements, signs of rickets, or intention to move from Ulaanbaatar within 4 years. Of 11 475 children invited to participate in the study, 9814 underwent QFT testing, and 8851 with negative results were included in the study. All but 1 participant in the placebo group completed follow-up and were included in the present analysis. Data were analyzed from November 2021 to February 2022.

INTERVENTIONS: Weekly oral doses of vitamin D3, 14 000 IU, (n = 4418), or placebo (n = 4433) for 3 years.

MAIN OUTCOMES AND MEASURES: Mean z scores for height for age, body mass index for age, and waist-to-height ratio; mean percentage body fat, fat mass, and fat-free mass; and mean Tanner scores for pubertal development.

RESULTS: Of 8851 participants, 4366 (49.3%) were female, and 8165 (92.2%) were of Khalkh ethnicity; the mean (SD) age was 9.4 (1.6) years. A total of 8453 participants (95.5%) were vitamin D deficient at baseline, and mean end-of-study 25(OH)D concentrations among participants randomized to vitamin D vs placebo were 31.0 vs 10.7 ng/mL (mean difference, 20.3; 95% CI; 19.9-20.6). However, vitamin D supplementation did not influence mean height for age, body mass index for age, waist-to-height ratio, percentage body fat, fat mass, fat-free mass, or Tanner scores, either overall or within subgroups defined by baseline 25(OH)D concentration less than 10 ng/mL vs 10 ng/mL or greater, estimated calcium intake less than 500 mg/d vs 500 mg/d or greater, or male vs female sex.

CONCLUSIONS AND RELEVANCE: In school-aged children in this study with low baseline vitamin D status, oral vitamin D3 supplementation at a dose of 14 000 IU per week for 3 years was effective in elevating 25(OH)D concentrations but did not influence growth, body composition, or pubertal development.

TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02276755.

Alternate JournalJAMA Pediatr
PubMed ID36441522
PubMed Central IDPMC9706398
Grant ListT32 DK007703 / DK / NIDDK NIH HHS / United States
R01 HL122624 / HL / NHLBI NIH HHS / United States