Dietary adequacy of vitamin D and calcium among Inuit and Inuvialuit women of child-bearing age in Arctic Canada: a growing concern

Arctic populations are at an increased risk of vitamin D inadequacy due to geographic latitude and a nutrition transition. This study aimed to assess the adequacy of dietary vitamin D and calcium among women of child-bearing age in Arctic Canada. This study collected data from 203 randomly selected women of child-bearing age (19-44 years) in Nunavut and the Northwest Territories of Arctic Canada. Cross-sectional surveys using a validated quantitative food frequency questionnaire were analysed to determine the dietary adequacy of vitamin D and calcium and summarize the top foods contributing to vitamin D and calcium intake among traditional food eaters (TFE) and non-traditional food eaters (NTFE). The response rate was between 69-93% depending on the community sampled. Mean BMIs for both TFE and NTFE were above the normal range. Traditional food eaters had a significantly higher median vitamin D intake compared with non-traditional eaters (TFE=5.13 ± 5.34 µg/day; NTFE=3.5 ± 3.22 µg/day, p=0·004). The majority of women (87%) were below the Estimated Average Requirements (EAR) for vitamin D. Despite adequate median daily calcium intake in both TFE (1,299 ± 798 mg/day) and NTFE (992 ± 704 mg/day; p=0.0005), 27% of the study population fell below the EAR for calcium. Dairy products contributed the most to intake of vitamin D (TFE=30.7%; NTFE=39.1%) and calcium (TFE=25.5%; NTFE=34.5%). Inadequate dietary vitamin D intake is evident among Inuit and Inuvialuit women of child-bearing age in Arctic Canada. Promotion of nutrient-rich sources of traditional foods, supplementation protocols and/or expanded food fortification should be considered to address this nutrition concern.