Vitamin D deficiency and lifestyle risk factors in a Norwegian adolescent population. Issue 7 (November 2014)

• Record Type: Journal Article
• Authors: Öberg, Johanna; Jorde, Rolf; Almås, Bjørg; Emaus, Nina; Grimnes, Guri
• Is Part Of: Scandinavian journal of public health. Volume 42:Issue 7(2014:Nov.)
• Page Start: 593
• Page End: 602
• Publication Date: 2014-11
• Subjects: Adolescents -- epidemiology -- parathyroid hormone -- population-based study -- risk factors -- vitamin D -- vitamin D deficiency; Public health -- Periodicals; Social medicine -- Periodicals; 614
• DOI: 10.1177/1403494814541593
• Languages: English
• ISSNs: 1403-4948

Abstract

Aim: The aim was to study vitamin D status in a healthy adolescent Norwegian population at 69°N. Methods : The data presented come from The Tromsø Study: Fit Futures, during the school year 2010/2011 (not including the summer months), where 1, 038 (92% of those invited) participated. Physical examinations, questionnaires and blood samples were collected, and serum 25-hydroxyvitamin D (25(OH)D) were analyzed using LC-MS/MS. Results : Results are presented from 475 boys and 415 girls (15–18 years old) with available blood samples. A total of 60.2% had vitamin D deficiency or insufficiency (serum 25(OH)D <50 nmol/l), 16.5% were deficient (<25 nmol/l) and 1.6% had severe vitamin D deficiency (<12.5 nmol/l). Only 12.4% had levels >75 nmol/l. A significant gender difference with a mean (SD) serum 25(OH)D level of 40.5 (20.5) nmol/l in boys and 54.2 (23.2) nmol/l in girls ( p <0.01) was present. Furthermore, 51.3% of girls had levels >50 nmol/l in comparison to 29.7% of boys ( p <0.01). There was an inverse correlation between parathyroid hormone levels and 25(OH)D, rs = −0.30 ( p <0.01). Explanatory factors that were significantly associated with serum 25(OH)D levels in multivariate models were use of snuff, consumption of vitamin D fortified milk, cod liver oil and vitamin/mineral supplements, physical activity, sunbathing holiday and use of solarium in boys, and vitamin/mineral supplements, physical activity, sunbathing holiday and use of solarium in girls . Conclusions : Vitamin D deficiency is prevalent during the school year among adolescents in northern Norway, particularly among boys.