Vitamin D status in Greenland is influenced by diet and ethnicity: a population-based survey in an Arctic society in transition

Vitamin D status as measured by plasma 25-hydroxyvitamin D (25(OH)D) is important to human health. Circumpolar people rely on dietary sources and societal changes in the Arctic are having profound dietary effects. The objective of the present study was to determine plasma 25(OH)D status and factors important to plasma 25(OH)D in populations in Greenland. Inuit and non-Inuit aged 50-69 years in the capital in West Greenland (latitude 64°15'N) and in a major town and remote settlements in East Greenland (latitude 65°35'N) were surveyed. Supplement use and lifestyle factors were determined by questionnaires. Inuit food scores were computed from a FFQ of seven traditional Inuit and seven imported food items. 25(OH)D₂ and 25(OH)D₃ levels were measured in the plasma. We invited 1 % of the population of Greenland, and 95 % participated. 25(OH)D₃ contributed 99·7 % of total plasma 25(OH)D. Non-Inuit had the lowest median plasma 25(OH)D of 41 (25th-75th percentile 23-53) nmol/l compared with 64 (25th-75th percentile 51-81) nmol/l in Inuit (P