Recent JAMA study evaluating health claims on fish oil supplements criticizing use of structure/function claims for lack of efficacy

Photo © iStockphoto.com/Juxtagirl

A recent cross-sectional study¹ published in JAMA Network evaluated 2819 fish oil supplements currently on the market (based on the National Institute of Health’s Dietary Supplement Label Database) for the frequency and types of claims used on fish oil supplements. Specifically, the researchers looked at the number of U.S. Food and Drug Administration (FDA)-reviewed qualified health claims versus structure/function claims, as well as the organ system referenced on the label. They also looked at the total daily dose of combined EPA and DHA in supplements from 16 leading brands.

Of the 2819 supplements, 2082 made at least one health claim. Of these, 399 used an FDA-approved qualified health claim and 1683 made structure/function claims, with cardiovascular health claims being the most common. When looking at the daily doses of EPA and DHA in 255 fish oil supplements from 16 leading brands, researchers found substantial variability in daily dose of EPA, DHA, and total EPA+DHA. According to the study, only 24 of the 255 supplements contained a daily dose of 2 g or more of EPA+DHA.

The study negatively frames the common use of structure/function claims on these products because they “imply a health benefit across a variety of organ systems despite a lack of trial data showing efficacy.” The researchers also asserted that the significant heterogeneity between the products in their daily doses may lead to “potential variability in safety and efficacy between supplements.” In the end, they suggested increased regulation of dietary supplement labeling to “prevent consumer misinformation.”

Industry advocates are critical of the study. The Council for Responsible Nutrition (CRN; Washington, D.C.) explains that structure/function claims and qualified health claims serve different purposes, with one providing non-disease specific health information, and the other discussing the relationship between a nutrient and disease risk. CRN notes that both must be supported by scientific evidence, but because of their different purposes, the level of substantiation is not the same.

“The call for ‘additional regulation of dietary supplement labeling’ is both predictable and unsupported by the research,” said Steve Mister, president and CEO of CRN, in a press release. “Consumers should always discuss their supplement regimens with their healthcare providers, but there is nothing in this study that should persuade consumers to change their omega-3 regimens for better health. Ultimately, this study demonstrates an amazing lack of understanding of the many different reasons why consumers choose to use supplements for better health.”

While the study criticized the claims made by the evaluated products, the claims are appropriate under current regulations and carried the appropriate legal disclaimers regarding the limitations of the claims. With regard to the heterogeneity of dosages, CRN points out that nutritional needs vary and consumers may not all have the same dosage requirements.

Harry B. Rice, vice president of regulatory affairs, for The Global Organization for EPA and DHA Omega-3s (GOED; Salt Lake City, UT) called the article "fraught with innaccuracies" in a recent communication from the organization. Rice accused the article of cherry picking evidence, citing instances where the authors mention studies that found no cardiovascular health benefits from fish oil supplementation while failing to mention the wealth of research supporting fish oil's health benefits. Rice also takes issue with the JAMA study mentioning the possible increased risk of atrial fibrillation at high doses without offering any clarification on a complicated topic that requires further investigation.

Reference

1. Assadourian, J.; Peterson, E.D.; McDonald, S.A.; Gupta, A.; Navar, A.M. Health Claims and Doses of Fish Oil Supplements in the US. JAMA Cardiol. 2023, Article ASAP. DOI: 10.1001/jamacardio.2023.2424 (accessed 2023-8-24)