Vitamin D status of Canadians employed in northern latitudes
Occup Med (Lond) (2013) doi: 10.1093/occmed/kqt106
Y. -S. Chao1,
L. Brunel2,
P. Faris3 and
P. J. Veugelers1
1 School of Public Health, University of Alberta, Edmonton, Alberta, Canada,
2 Santessence, Calgary, Alberta, Canada,
3 Alberta Health Services, Calgary, Alberta, Canada.
Correspondence to: Y.-S. Chao, School of Public Health, University of Alberta, 3–50 University Terrace, 8303-112 St, Edmonton, Alberta T6G 2T4, Canada. Tel: +1 780 492 4302; fax: +1 780 492 5521; e-mail: chaoyisheng at gmail.com
Background Vitamin D deficiency and insufficiency are prevalent worldwide, but relatively few studies have examined vitamin D status in working populations.
Aims To assess the prevalence of vitamin D deficiency and insufficiency in Canadian workers and investigate risk factors in this population.
Methods A cross-sectional study using data from a health programme enrolling workers mostly from Northern Alberta, Canada. As part of the programme, volunteers were invited to complete a lifestyle questionnaire. Blood was taken to determine plasma 25-hydroxyvitamin D (25(OH)D) levels. Logistic and linear regressions were used to investigate the relationships between individual characteristics and vitamin D status.
Results Between October 2007 and December 2012, 6101 eligible workers enrolled in the health programme. The prevalence of vitamin D deficiency (plasma 25(OH)D, levels <27.5 nmol/l) and insufficiency (<37.5 nmol/l) were 3 and 8%, respectively. Male employees were significantly more likely to be vitamin D deficient and insufficient than females. Residing at a more northern latitude increased the likelihood of vitamin D deficiency and insufficiency. Age, assessments made in summer, better general health and physical activity and use of vitamin D supplementation were all related to lower likelihood of deficiency and insufficiency.
Conclusions Vitamin D deficiency and insufficiency are a concern in this sample of Canadian workers. Vitamin D supplementation is recommended to reduce the prevalence of deficiency and insufficiency in this group.
This study has far higher vitamin D levels than in the Southern portion of Canada.
No indication in the abstract if the participants were taking vitamin D supplements
See also VitaminDWiki
- Vitamin D blood levels of Canadians – Jan 2013 which shows that about 50% of that age group has < 50 nmol/l
whereas this study of Northern workers has only 8% < 37.5 nmol/l