title: Estimation of the dietary requirement for vitamin D in white children aged 4-8 y: a randomized, controlled, dose-response trial.
abstract: Children in northern latitudes are at high risk of vitamin D deficiency during winter because of negligible dermal vitamin D3production. However, to our knowledge, the dietary requirement for maintaining the nutritional adequacy of vitamin D in young children has not been investigated.
  
  
  
  We aimed to establish the distribution of vitamin D intakes required to maintain winter serum 25-hydroxyvitamin D [25(OH)D] concentrations above the proposed cutoffs (25, 30, 40, and 50 nmol/L) in white Danish children aged 4-8 y living at 55°N.
  
  
  
  In a double-blind, randomized, controlled trial 119 children (mean age: 6.7 y) were assigned to 0 (placebo), 10, or 20 μg vitamin D3/d supplementation for 20 wk. We measured anthropometry, dietary vitamin D, and serum 25(OH)D with liquid chromatography-tandem mass spectrometry at baseline and endpoint.
  
  
  
  The mean ± SD baseline serum 25(OH)D was 56.7 ± 12.3 nmol/L (range: 28.7-101.4 nmol/L). Serum 25(OH)D increased by a mean ± SE of 4.9 ± 1.3 and 17.7 ± 1.8 nmol/L in the groups receiving 10 and 20 μg vitamin D3/d, respectively, and decreased by 24.1 ± 1.2 nmol/L in the placebo group (P < 0.001). A nonlinear model of serum 25(OH)D as a function of total vitamin D intake (diet and supplements) was fit to the data. The estimated vitamin D intakes required to maintain winter serum 25(OH)D >30 (avoiding deficiency) and >50 nmol/L (ensuring adequacy) in 97.5% of participants were 8.3 and 19.5 μg/d, respectively, and 4.4 μg/d was required to maintain serum 25(OH)D >40 nmol/L in 50% of participants.
  
  
  
  Vitamin D intakes between 8 and 20 μg/d are required by white 4- to 8-y-olds during winter in northern latitudes to maintain serum 25(OH)D >30-50 nmol/L depending on chosen serum 25(OH)D threshold. This trial was registered at clinicaltrials.gov as NCT02145195.
authors.affiliation: Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark; cmo@nexs.ku.dk.|Department of Nutrition and Midwifery, Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark.
authors.forename: Charlotte
authors.identifier: 0000-0003-4965-4331
authors.initials: C
authors.lastname: Mortensen
authors.affiliation: Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Camilla T
authors.identifier: 0000-0002-5013-0562
authors.initials: CT
authors.lastname: Damsgaard
authors.affiliation: Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Hanne
authors.identifier: 0000-0002-1680-587X
authors.initials: H
authors.lastname: Hauger
authors.affiliation: Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Christian
authors.identifier: 0000-0002-5095-0624
authors.initials: C
authors.lastname: Ritz
authors.affiliation: Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Surrey, United Kingdom.
authors.forename: Susan A
authors.initials: SA
authors.lastname: Lanham-New
authors.affiliation: Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Surrey, United Kingdom.
authors.forename: Taryn J
authors.initials: TJ
authors.lastname: Smith
authors.affiliation: Cork Centre for Vitamin D and Nutrition Research, School of Food and Nutritional Sciences.
authors.forename: Áine
authors.initials: Á
authors.lastname: Hennessy
authors.affiliation: Cork Centre for Vitamin D and Nutrition Research, School of Food and Nutritional Sciences.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Dowling
authors.affiliation: Cork Centre for Vitamin D and Nutrition Research, School of Food and Nutritional Sciences.|Department of Medicine, and.
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Cashman
authors.affiliation: Cork Centre for Vitamin D and Nutrition Research, School of Food and Nutritional Sciences.|Irish Centre for Fetal and Neonatal Translational Research, University College Cork, Cork, Ireland.
authors.forename: Mairead
authors.initials: M
authors.lastname: Kiely
authors.affiliation: Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Christian
authors.identifier: 0000-0002-5311-9457
authors.initials: C
authors.lastname: Mølgaard
mesh_terms: D002648:Child; D002675:Child, Preschool; D003718:Denmark; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D006801:Humans; D017711:Nonlinear Dynamics; D009751:Nutritional Requirements; D012621:Seasons; D013472:Sunlight; D016896:Treatment Outcome; D014807:Vitamin D / Q000008:administration & dosage* / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood; D044465:White People
chemical_list: D014807:Vitamin D
keywords: ODIN; children; dose-response; randomized controlled trial; recommendations; requirement; vitamin D