Household food insecurity is generally associated with poorer quality diets in Canada, but whether household food insecurity heightens the probability of inadequate micronutrient intakes is unknown. The objective of this research was to investigate how prevalence of micronutrient inadequacy differed by severity of household food insecurity among adults in Canada. Using the 2015 Canadian Community Health Survey Nutrition, this study included participants aged 19-64 years who completed up to two 24 h dietary recalls and provided details about household food insecurity (n = 9486). Children and older adults were not included due to sample size limitations. Usual micronutrient intake distributions were estimated by a four-level measure of food insecurity status using the National Cancer Institute method. Welch's t tests assessed differences in prevalence of inadequacy for selected micronutrients. Prevalence differed for some micronutrients among those living in marginally and moderately food insecure compared to food-secure households. The greatest differences in prevalence of inadequacy were observed between severely food-insecure and food-secure households: vitamin A (60.0%, SE = 11.9 vs. 40.6%, SE = 2.7, p < 0.0001), vitamin B6 (42.7%, SE = 9.1 vs. 12.8%, SE = 2.5, p < 0.0001), folate (39.4%, SE = 10.0 vs. 15.9%, SE = 2.2, p < 0.0001), vitamin C (63.3%, SE = 5.2 vs. 29.1%, SE = 2.8, p < 0.0001), calcium (78.6%, SE = 6.4 vs. 58.7%, SE = 1.3, p < 0.0001), magnesium (75.6%, SE = 9.5 vs. 48.7%, SE = 1.2, p < 0.0001), and zinc (34.9%, SE = 10.0 vs. 23.2%, SE = 2.4, p = 0.0009). Apparent underreporting also differed by severity of food insecurity, with increased underreporting observed with worsening food insecurity. The probability of inadequate micronutrient intakes among adults rises sharply with more severe household food insecurity in Canada.
Keywords: National Cancer Institute method; household food insecurity; micronutrient inadequacy; prevalence of inadequacy; usual intake.