Background: Vitamin D status in groups of northern indigenous people of Russia leading close to traditional (seminomadic reindeer herding), post-traditional (in settlements) or "modernized" (in towns) way of life was analysed.
Design: The survey study groups consisted of 178 Nenets and Komi aged 18-60 living in the Arctic (66-67°N). Urban Komi, Udmurts and Komi-Permiaks (n=150) living in a non-Arctic area (57-61°N) formed a control group. The concentration of serum 25-hydroxyvitamin D (25OHD), as a transport form of vitamin D, was assessed by enzyme immunoassay analysis.
Results: The group average 25OHD levels in both rural and urban Arctic residents are within the range of values seen in the non-Arctic urban subjects adjusted for season: 39.7-47.7 nmol/l. Abandoning traditional lifestyle associates with lower vitamin D levels in indigenous Arctic people. Mean±standard deviation 25OHD values among Nenets were lower in those living in the administrative centre (a big settlement) with a population of 1,460 (32.2±12.90 nmol/l) than in the residents of small settlements (39.6±14.08 nmol/l), and in reindeer herders (42.4±13.45 nmol/l; p<0.05 in both cases). Komi townspeople had lower 25OHD concentrations (47.7±12.00 nmol/l) than Komi reindeer herders (68.7±25.20; p<0.01).
Conclusion: The transition from seminomadic to post-traditional and "modernized" way of life has led to a decrease in the consumption of traditional foods among the indigenous people of the Russian Arctic. Our data support the notion that the traditional northern diet promotes healthy vitamin D levels, while adherence to the "western" type of diet correlates with a lower 25OHD concentration.
Keywords: 25OHD; Arctic; circumpolar regions; lifestyle; nutrition; reindeer herders.