While significant research has pointed out fish oil’s nil benefits in cardiovascular health, this hasn’t stopped supplement industry marketers from waxing poetic about their ‘value’ in this goldmine of heart health.

Fish oil supplements are a multi-million dollar industry. Many people down them daily believing the omega-3 fatty acids they contain are good for their overall health, particularly for their heart.

While it’s true people who eat seafood regularly are less likely to die of heart disease, studies have not shown that taking fish oil as a supplement offers the same benefit. Even so, fish oil marketers continue to make health claims that imply a wide range of benefits, according to a study published in JAMA Cardiology.2

An evaluation by Washington Post writer Lindsey Bever said researchers analysed labels from more than 2,000 fish oil supplements that made health claims. They found that more than 80 percent used what is known as a “structure and function claim,” which is 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, which accounted for 62 percent, were the most common.

Cardiovascular disease risk

Fish oil contains two omega-3 fatty acids, EPA and DHA, found naturally in fatty fish such as salmon. Higher levels of these omega-3s have been associated with a lower risk of cardiovascular disease, but some experts say the observational findings are based on omega-3 levels in the diet, not from supplement use. In fact, two recent large clinical trials showed that over-the-counter fish oil supplements do not improve cardiovascular outcomes.

However, according to senior study author Ann Marie Navar, an associate professor of cardiology at the University of Texas Southwestern Medical Center, the vague wording used by fish oil marketers could lead to misinformation about the dietary supplement’s role.

“It is true that omega-3 fatty acids are present in the brain and are important for all sorts of brain functions,” she said. “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 decided to inventory claims made on fish oil supplement labels after continually hearing from her patients that they were taking it for their heart health—and then seeing their surprise when she advised them that there probably were none.

Through her research, Navar said, she was “alarmed” to learn that fish oil supplement labels often include claims that imply health benefits for a wide range of organ systems, including the heart, brain and eyes.

“It’s not surprising to me that my patients think fish oil is helping them,” she said.