Vitamin D status and functional health outcomes in children aged 2–8 y: a 6-mo vitamin D randomized controlled trial

• Published in: The American journal of clinical nutrition 2018-03, Vol.107 (3), p.355-364
• Main Authors: Brett, Neil R, Parks, Colleen A, Lavery, Paula, Agellon, Sherry, Vanstone, Catherine A, Kaufmann, Martin, Jones, Glenville, Maguire, Jonathon L, Rauch, Frank, Weiler, Hope A
• Format: Article
• Language: English
• Subjects: 25-hydroxyvitamin D; Absorptiometry, Photon; Anthropometry; Biomarkers; Biomarkers - blood; Body Composition; Body mass index; Body size; bone; Bone and Bones - physiology; Bone composition; Bone Density; Bone mass; Canada; Cheese; Child; Child, Preschool; Children; Childrens health; Chromatography; Clinical trials; Computed tomography; Cross-Sectional Studies; Deposition; Diet; Dietary intake; Double-Blind Method; Dual energy X-ray absorptiometry; DXA; Energy measurement; Female; Food; Food, Fortified; Fortified foods; Health Surveys; Humans; Liquid chromatography; Male; Mass spectrometry; Mass spectroscopy; Metabolites; muscle; Muscles; Musculoskeletal system; Physical activity; randomized controlled trial; Seasons; Socioeconomic Factors; Sunlight; Tibia; Treatment Outcome; Vitamin D; Vitamin D - administration & dosage; Vitamin D - blood; Yogurt
• ISSN: 0002-9165; 1938-3207
• DOI: 10.1093/ajcn/nqx062

Most Canadian children do not meet the recommended dietary intake for vitamin D. The aims were to test how much vitamin D from food is needed to maintain a healthy serum 25-hydroxyvitamin D3 [25(OH)D3] status from fall to spring in young children and to examine musculoskeletal outcomes. Healthy children aged 2–8 y (n = 51) living in Montreal, Canada, were randomly assigned to 1 of 2 dietary vitamin D groups (control or intervention to reach 400 IU/d by using vitamin D–fortified foods) for 6 mo, starting October 2014. At baseline and at 3 and 6 mo, anthropometric characteristics, vitamin D metabolites (liquid chromatography–tandem mass spectrometry), and bone biomarkers (IDS-iSYS, Immunodiagnositc Systems; Liaison; Diasorin) were measured and physical activity and food intakes surveyed. At baseline and at 6 mo, bone outcomes and body composition (dual-energy X-ray absorptiometry) were measured. Cross-sectional images of distal tibia geometry and muscle density were conducted with the use of peripheral quantitative computed tomography scans at 6 mo. At baseline, participants were aged 5.2 ± 1.9 (mean ± SD) y and had a body mass index z score of 0.65 ± 0.12; 53% of participants were boys. There were no differences between groups in baseline serum 25(OH)D3 (66.4 ± 13.6 nmol/L) or vitamin D intake (225 ± 74 IU/d). Median (IQR) compliance was 96% (89–99%) for yogurt and 84% (71–97%) for cheese. At 3 mo, serum 25(OH)D3 was higher in the intervention group (P