CRN criticizes study claiming multivitamins offer no measurable health outcomes

In response to the study, the Council for Responsible Nutrition issued a statement citing the study’s limitations and asserting that the study’s unfounded claims in no way discount the benefits multivitamins have for human nutrition.

A recent study published in the British Journal of Medicine1 found that multivitamin supplementation had no clinically measurable outcomes despite multivitamin users self-reporting 30% better overall health compared to non-users. This led the researchers to conclude that widespread use of multivitamins in adults is the result of individuals’ positive expectations that multivitamin use leads to better health outcomes or a self-selection bias. In response, the Council for Responsible Nutrition (CRN; Washington, D.C.) issued a statement citing the study’s limitations and asserting that the study’s unfounded claims in no way discount the benefits multivitamins have for human nutrition. 

“The multivitamin continues to be one of the most popular dietary supplements among Americans and plays an important role in promoting and preserving good health, and for good reason. CRN stresses that the findings of the recent study in no way discount the multivitamin’s many benefits in combatting insufficient nutrient levels and promoting optimum health, nor does it provide basis for consumers to reconsider their decision to take a multivitamin or to take one in the future,” said Andrea Wong, PhD, senior vice president, scientific and regulatory affairs, CRN, in her statement. “The many limitations and shortcomings that hinder this study must be taken into account, only some of which are acknowledged by the study’s own authors. For instance, the results of the study are based on survey data, so rather than being determined by a clinician, all measured outcomes are self-reported and therefore, less reliable. The study also does not capture the composition of the multivitamin or multimineral products reported by respondents or the duration or frequency of consumption. It is impossible to know which products were taken or how often respondents took them over the 12-month period covered by the survey, or even how long the subjects had previously been on their regimens. Additionally, the cross-sectional design of this study only provides a snapshot in time of multivitamin use and health outcomes, preventing any determination of causality.”

For that matter, continues Wong, the primary role of multivitamins is to fill nutrient gaps, and the recent 2020 Scientific Report from the Dietary Guidelines Advisory Committee (DGAC) identified vitamins A, C, D, E, and K, calcium, magnesium, dietary fiber, choline and potassium as under-consumed nutrients.

“Most multivitamin products contain many of the shortfall nutrients identified by the DGAC and can help Americans fill in nutrient gaps that they consistently fall short on through dietary intake only,” says Wong. “The conclusions of the study are a disservice to the public and should not influence consumers’ decision to take a multivitamin or other dietary supplement product. As data continues to show that Americans, particularly low-income populations, do not get the essential nutrients needed from diet alone, taking a multivitamin is a convenient and affordable way to ensure consumers get the nutrients they need.”

Reference

  1. Paranjpe MD et al. “Self-reported health without clinically measurable benefits among adult users of multivitamin and multimineral supplements: a cross-sectional study.” British Journal of Medicine, vol. 10 (2020)