Bottle to body: how multivitamin/mineral supplements shape Canadian nutrient intake

Multivitamin/mineral (MVM) supplements are widely used in North America, presenting important implications for the practice of primary care, especially in Canada where practitioners frequently serve as patients' initial source of health guidance. The aim of this study is to determine the prevalence of MVM supplement use and the nutrient contribution of MVM supplements to the nutrient intake of Canadians. Dietary data from respondents >1 year in the Canadian Community Health Survey 2015 were used to estimate the prevalence of nutrient adequacy and intakes greater than the upper limit (UL). The National Cancer Institute method was used to estimate usual intakes of vitamin A, C, and magnesium. The prevalence of MVM consumption, as well as any individual vitamin and mineral supplement use, were 24.78% and 19.16%, respectively. Usage was most common among children aged 1-8 years and women over 51 years, particularly among nonobese children and higher-income households. Supplement users show a lower prevalence of nutrient inadequacy from dietary sources alone compared to nonusers of supplements. Also, supplement use is associated with a lower prevalence of nutrient inadequacy compared to nonusers. This study highlights that while MVM supplement use does contribute to overall dietary intake, current MVM supplement use is generally associated with markers of higher socio-economic status and thus those already consuming a healthy diet and less likely to need MVM supplemental nutrients. Aside from population subgroups with specific supplement recommendations (e.g., folic acid in women of childbearing age), dietary guidelines should continue to emphasize meeting nutrient requirements from a wide variety of foods.