title: Vitamin D status of Icelandic children and its influence on bone accrual.
abstract: The importance of vitamin D for children's bone health has been well established, but the effects of less severe deficiency are not fully known. The main objective of this study was to assess the vitamin D status of Icelandic children at the age of 7, and again at 9 years of age, and the association of vitamin D status with bone mineral content and bone accrual over 2 years. We invited 321 children to participate in this study, and 267 (83 %) took part; 211 (79 %) underwent a DXA scan and 164 were again scanned 2 years later; 159 (60 %) vitamin D samples were measured and 119 (75 %) were measured again 2 years later. At age 7, 65 % of the children had vitamin D concentrations <50 nmol/l, and at age 9 this figure was 60 %. At age 7, 43 % of the children had insufficient amounts of vitamin D (37.5-50 nmol/l), and 22 % had a vitamin D deficiency (<37.5 nmol/l). In linear regression analysis, no association was found between vitamin D and bone mineral content. Furthermore, there was no significant difference in bone accrual over 2 years for the children with insufficient or deficient vitamin D at both ages, compared to those having more than 50 nmol/l at both time points. More than 60 % of Icelandic children have inadequate concentrations of vitamin D in serum repeatedly over a 2-year interval. However, vitamin D in the range did not have a significant effect on bone mineral content or accrual at ages 7 and 9.
authors.affiliation: Solvangur Health Care Center, Hafnarfjordur, Iceland.
authors.forename: Haukur Heidar
authors.initials: HH
authors.lastname: Hauksson
authors.affiliation: Seltjarnarnes Health Care Center, Seltjarnarnes, Iceland.|Center for Research in Sport and Health Sciences, School of Education, University of Iceland, Reykjavik, Iceland.
authors.forename: Hannes
authors.initials: H
authors.lastname: Hrafnkelsson
authors.affiliation: Center for Research in Sport and Health Sciences, School of Education, University of Iceland, Reykjavik, Iceland.
authors.forename: Kristjan Thor
authors.initials: KT
authors.lastname: Magnusson
authors.affiliation: Center for Research in Sport and Health Sciences, School of Education, University of Iceland, Reykjavik, Iceland.
authors.forename: Erlingur
authors.initials: E
authors.lastname: Johannsson
authors.affiliation: Solvangur Health Care Center, Hafnarfjordur, Iceland. emilsig@hi.is.|Department of Family Medicine, University of Iceland, Reykjavik, Iceland. emilsig@hi.is.
authors.forename: Emil L
authors.initials: EL
authors.lastname: Sigurdsson
mesh_terms: D015519:Bone Density; D002648:Child; D005260:Female; D006801:Humans; D007055:Iceland; D008297:Male; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: 25(OH)-D; BMC; Bone accrual; Children; Vitamin D