Voluntary food fortification in the United States: potential for excessive intakes.

BACKGROUND: Historically, the voluntary addition of micronutrients to foods in the United States has been regarded as an important means to lessen problems of nutrient inadequacy. With expanding voluntary food fortification and widespread supplement use, it is important to understand how voluntary food fortification has an impact on the likelihood of excessive usual intakes. Our objective was to investigate whether individuals in the United States with greater frequency of exposure to micronutrients from voluntarily fortified foods (vFF) are more likely to have usual intakes approaching or exceeding the respective tolerable upper intake levels (UL). SUBJECTS/METHODS: The National Cancer Institute method was applied to data from the 2007-2008 National Health and Nutrition Examination Survey (NHANES) to estimate the joint distribution of usual intake from both vFF and non-vFF sources for 12 nutrients and determine the probability of consuming these nutrients from vFF on a given day. For each nutrient, we estimated the distribution of usual intake from all food sources by quintile of probability of consuming vFF and compared the distributions with ULs. RESULTS: An increased probability of consuming zinc, retinol, folic acid, selenium and copper from vFF was associated with a greater risk of intakes above the UL among children. Among adults, increased probability of consuming calcium and iron from vFF was associated with a greater risk of intakes above the UL among some age/sex groups. CONCLUSION: The high nutrient exposures associated with vFF consumption in some population subgroups suggest a need for more careful weighing of the risks and benefits of uncontrolled food fortification.

Discretionary addition of vitamins and minerals to foods: implications for healthy eating.

OBJECTIVES: Health Canada proposes to allow manufacturers to add vitamins and minerals to a wide variety of foods at their discretion, a practice that has long been permitted in the United States and Europe. With Health Canada's proposed exclusion of staple and standardized foods from discretionary fortification, questions arise about the nutritional quality of the foods that remain eligible for fortification. To better understand the implications of this policy for healthy eating, this study examined the contribution of foods eligible to be fortified to the dietary quality of Canadians. METHODS: Using 24-h dietary recall data from the 2004 Canadian Community Health Survey, the relationship between intake of fortifiable foods and indicators of dietary quality was assessed. RESULTS: The mean percentage contribution of fortifiable foods to usual energy intake ranged from 19% among men over the age of 70 years to 36% for girls aged 14-18 years. Fortifiable food (as a percentage of total energy) was inversely associated with intake of vegetables and fruit, meat and alternatives, milk products, fiber, vitamins A, B6, B12 and D, magnesium, potassium and zinc. Fortifiable food was positively associated with dietary energy density, total energy intake and grain products. Few relationships were found for folate, vitamin C, iron, calcium, sodium and saturated fat. CONCLUSIONS: Consumption of foods slated for discretionary fortification is associated with lower nutrient intakes and suboptimal food intake patterns. Insofar as adding nutrients to these foods reinforces their consumption, discretionary fortification might function to discourage healthier eating patterns.