Despite the widespread belief that over-the-counter fish oil supplements offer significant cardiovascular benefits, a new study published in JAMA Cardiology exposes the disconnect between marketing claims and scientific evidence.
The sale of fish oil supplements has grown into a multibillion-dollar industry, with many individuals incorporating fish oil capsules into their daily routines in the hope of improving their overall health, particularly their heart health.
While it is well-established that individuals who consume seafood regularly may have a reduced risk of heart disease, research has not shown the same advantages for fish oil supplements. Nevertheless, marketers in the fish oil industry continue to make health claims that suggest a wide range of benefits, as revealed by the recent study.
Researchers analyzed labels from over 2,000 fish oil supplements that made health claims, discovering that more than 80 percent of these products utilized what is known as a “structure and function claim.” These claims offer a general description of the role of omega-3 fatty acids in the body, such as “promotes heart health” or “supports heart, mind, and mood.” Cardiovascular health claims, accounting for 62 percent, were the most prevalent.
Fish oil contains two essential omega-3 fatty acids, EPA and DHA, naturally found in fatty fish like salmon. Elevated levels of these omega-3s have been associated with a lower risk of cardiovascular disease, but the observational findings are based on dietary intake, not supplement use. In fact, recent large clinical trials have shown that over-the-counter fish oil supplements do not lead to improved cardiovascular outcomes.
The study highlights the vagueness of the wording used by fish oil marketers, which could potentially misinform consumers about the dietary supplement’s role. Ann Marie Navar, associate professor of cardiology at the University of Texas Southwestern Medical Center and senior author of the study, expressed concern about the situation.
“It is true that omega-3 fatty acids are present in the brain and are important for all sorts of brain functions,” Navar explained. “What has not been consistently shown with high-quality trials is that taking more of it in the form of a fish oil supplement leads to improved performance or prevention of disease.”
Navar and her colleagues conducted the inventory of claims made on fish oil supplement labels after noting that patients were often taking fish oil for heart health benefits despite the lack of solid evidence.
The study’s findings underscore the need for consumers to exercise caution when interpreting health claims related to dietary supplements and to consult healthcare professionals for evidence-based guidance.
Previous research on fish oil supplements has yielded conflicting results regarding their effectiveness for heart health, and recent scientific data have cast further doubts. A randomized trial involving over 15,000 patients with diabetes, a cardiovascular disease risk factor, showed no significant difference in the risk of a serious cardiovascular event between those taking an omega-3 supplement and those who were not. Another randomized trial with over 25,000 participants found that supplementation did not reduce the risk of major cardiovascular events or cancer.
