title: Randomized controlled trial of the effects of vitamin D–fortified milk and bread on serum 25-hydroxyvitamin D concentrations in families in Denmark during winter: the VitmaD study.
abstract: BACKGROUND
  Vitamin D intakes are lower than dietary recommendations in most populations, and thus, a low vitamin D status is widespread, especially during winter.
  
  
  OBJECTIVE
  We investigated the effects of increasing vitamin D intake to the recommended amount by fortification of milk and bread on serum 25-hydroxyvitamin D [25(OH)D] concentrations in families during winter in Denmark.
  
  
  METHODS
  The study was a randomized controlled trial in 782 children and adults (4-60 y old) recruited as 201 families. Families were randomly assigned to vitamin D-fortified or nonfortified milk and bread for 6 mo starting in September. The milk and bread replaced the participants' usual consumptions of products.
  
  
  RESULTS
  Median (IQR) vitamin D intakes (habitual diet plus fortified products) were 9.4 mg/d (6.5, 12.3 mg/d) and 2.2 mg/d (1.5, 3.0 mg/d) in fortification and control groups, respectively. Geometric mean (IQR) serum 25(OH)D concentrations decreased from 73.1 nmol/L (61.9, 88.5 nmol/L) to 67.6 nmol/L (56.2, 79.4 nmol/L) in the fortification group and from 71.1 nmol/L (61.2, 85.9 nmol/L) to 41.7 nmol/L (29.5, 58.9 nmol/L) in the control group (both P , 0.001). The final 25(OH)D concentration was significantly higher in the fortification group than in the control group (P , 0.001). By the end of the study, ,1% of subjects in the fortification group and 25% of subjects in the control group had 25(OH)D concentrations ,30 nmol/L and 16% and 65% of subjects, respectively, had 25(OH)D concentrations ,50 nmol/L.
  
  
  CONCLUSIONS
  Vitamin D fortification of milk and bread reduces the decrease in serum 25(OH)D concentrations during winter and ensures 25(OH)D concentrations .50 nmol/L in children and adults in Denmark.
authors.affiliation: Division of Nutrition, National Food Institute, Technical University of Denmark, Mørkhøj Bygade 19, DK-2860 Søborg, Denmark. kjma@food.dtu.dk
authors.forename: Katja H
authors.initials: KH
authors.lastname: Madsen
authors.forename: Lone B
authors.initials: LB
authors.lastname: Rasmussen
authors.forename: Rikke
authors.initials: R
authors.lastname: Andersen
authors.forename: Christian
authors.initials: C
authors.lastname: Mølgaard
authors.forename: Jette
authors.initials: J
authors.lastname: Jakobsen
authors.forename: Poul J
authors.initials: PJ
authors.lastname: Bjerrum
authors.forename: Elisabeth W
authors.initials: EW
authors.lastname: Andersen
authors.forename: Heddie
authors.initials: H
authors.lastname: Mejborn
authors.forename: Inge
authors.initials: I
authors.lastname: Tetens
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001939:Bread; D002648:Child; D002675:Child, Preschool; D003718:Denmark; D004032:Diet; D019587:Dietary Supplements; D005260:Female; D005527:Food, Fortified; D006801:Humans; D008297:Male; D008875:Middle Aged; D008892:Milk / Q000737:chemistry*; D015596:Nutrition Assessment; D010349:Patient Compliance; D012621:Seasons; D014807:Vitamin D / Q000008:administration & dosage* / Q000097:blood*; D055815:Young Adult
chemical_list: D014807:Vitamin D