Nutritional implications of dietary gluten avoidance among Canadians: results from the 2015 Canadian Community Health Survey.

Adherence to a gluten-free diet (GFD) is the only available treatment for gluten-related disorders, although a GFD may also be followed for discretionary reasons. The main objectives of this study were to 1) describe and test for differences in key nutrient intakes among Canadians who follow a GFD compared to Canadians with no dietary exclusions; and 2) describe additional dietary avoidances, such as meat, poultry, fish, shellfish, eggs or dairy, adhered to by Canadians who avoid gluten. We conducted a secondary analysis of the cross-sectional 2015 Canadian Community Health Survey-Nutrition Survey, which included a general health survey and 24-hour dietary recall (n=20,487). Participants were categorized as those who avoid dietary gluten and those who reported no avoidances. Key nutrient intakes assessed, as a percent of Dietary Recommended Intakes, included fibre, B vitamins, vitamin D, calcium, iron, sodium, and zinc, and compared between the two groups using t-tests. Canadians who avoided gluten had significantly lower intakes of folate, vitamin B12, vitamin D, iron, sodium and calcium compared with those who did not avoid any food groups. However, Canadians who reported following a GFD were significantly more likely to use vitamin or mineral supplements in the past 30 days. More than 20% of those who avoided gluten also avoided dairy products. Findings suggest that following a GFD places Canadians at risk for nutrient inadequacies, particularly folate, calcium, and vitamin D. Further research is required to further examine how multiple dietary avoidances among those who avoid gluten may contribute to dietary inadequacies.