Consumers are Right: Research Confirms Dietary Supplements Help Meet Nutrient Needs
The choice of using dietary supplements to meet nutrient requirements is contentious. Maybe not as emotional as politics, religion, and taxes but many personal belief systems prevail when it comes to advice on dietary habits. Most health professionals, and journalists, prefer food-based solutions. Makes sense but then one has to navigate the merits of natural foods, organic foods, processed foods, minimally-processed foods, and locally-sourced foods. All of this is confusing. Could a multi-vitamin supplement serve as an insurance policy? Research supports the concept that supplement users are seeking nutritional adequacy to support health.
Pouchieu and colleagues sought to understand the factors determining dietary supplement use in France. Using self-reported dietary intake data from 79,786 adults (18y+) living in France, they report that dietary supplement use was positively associated with knowledge of nutritional recommendations and healthier lifestyle behaviors (non-smoking, physical activity, and moderate alcohol consumption). 40.8% of the population used dietary supplements during the past 12 mo, 25% more than 3 times per week. The primary reasons were to overcome tiredness (41.5%), stay healthy (33.8%), and to solve or overcome health problems (32.3%). Dietary supplement users were predominantly female, older, more educated, and morel likely to eat fruit, vegetables, and whole-grain foods. Dietary supplement users were less likely to have inadequate intakes of many vitamins and minerals.
These are similar to US findings (NHANES 2003-2006) where more than half of adults use dietary supplements. Bailey and colleagues reported that nutrient intakes from foods were higher in men (vitamins A, E and K) and women (vitamins A, C, D, and E) who use supplements and total nutrient intakes (food and supplement) were higher for every vitamin examined. Kennedy and colleagues examined US dietary supplement use patterns (NHANES 2007-2008). Supplement users consumed greater amounts of 8 nutrients (vitamins A, B12, C, E, folic acid, calcium, iron and zinc) than non-users. Supplement users were more likely to be female, older, white, more educated, higher income, and living in a food-secure household.
A reason many health professionals oppose supplementation is their concern about excessive intakes. The Tolerable Upper Limit (UL) is the highest average daily nutrient intake level that is likely to pose no risk of adverse health effects. The UL is a reasonable warning line in the sand. It is not a cliff edge into toxicity. It is important for nutrition guidance policy to be mindful of those exceeding the UL with consideration of others who are at risk because of nutritional inadequacy (below Estimated Average Requirement, EAR).
With the exception of folic acid with which cereal grains are fortified by US law to reduce the prevalence of babies being born with neural tube defects, Bailey and colleagues found fewer than 5-6% of Americans exceeding the UL. It isn’t prudent to reduce folic acid levels in fortified cereals because despite fortification and folic acid supplement recommendations for women of child-bearing age, many women still have low red blood cell folate status in early pregnancy (Branum et al, 2013). In an examination of the contributions of food sources (naturally-occurring as well as fortified and enriched) and dietary supplements, Fulgoni and associates report that enriched and fortified foods are important contributors to nutrient intakes. Dietary supplement use further diminishes the risk of nutrient inadequacy and the percentage of people exceeding the UL is very low.
Choosing to supplement their diet is the right choice for many people. For those who are presently using supplements, they should remember balance and moderation. More is not always better. The real travesty is that people who are not currently using supplements need them the most. People should not be deterred from using supplements. They should be encouraged to use them wisely and to avoid pharmacologic doses.
Pouchieu C, Andreeva VA, Peneau S, Kesse-Guyot E, Lassale C, Hercberg S, Touvier M. Sociodemographic, lifestyle and dietary correlates of dietary supplement use in a large sample of French adults: results from the NutriNet-Sante Cohort study. 2013 Br J Nutr doi:10.1017/S0007114513000615
Bailey RL, Fulgoni III VL, Keast DR, Dwyer JT. Examination of vitamin intakes among US adults by dietary supplement use. 2012 J Acad Nutr Diet doi:10.1016/j.jand.2012.01.026
Kennedy ET, Luo H, Houser RF. Dietary supplement use pattern of US adult population in the 2007-2008 National Health and Nutrition Examination Survey (NHANES). 2013 Ecol Food Nutr doi:10.1080/03670244.2012.706000
Branum AM, Bailey R, Singer BJ. Dietary supplement use and folate status during pregnancy in the United States. 2013 J Nutr doi:10.3945/jn.112.169987
Fulgoni III VL, Keast DR, Bailey RL, Dwyer J. Foods, fortificants, and supplements: Where do Americans get their nutrients? 2011 J Nutr doi:10.3945/jn.111.142257