Lawsuits in the US are challenging claims by fish oil supplement companies that their products support heart health, suggesting that instead, the opposite might be true.
Decades of research has shown that eating fish high in omega-3 fatty acids is good for your heart and may even prevent heart disease, but whether you derive the same cardiovascular benefits from a fish oil supplement is now under a legal microscope.
Marketers of fish oil supplements claim that their products support “heart health” or a “healthy heart” and may even reduce the risk of coronary heart disease, and their advertising seems to be working, with a recent study showing one in five Americans over 60 takes a fish oil supplement, often for heart health.
But do the products themselves work?
“While eating fish promotes (a) healthy heart, taking fish oil capsules does not,” alleges a lawsuit filed against the makers of Nature Made fish oil supplements in January.
Truth in Advertising reports that the lawsuit cites “overwhelming evidence” that it claims demonstrates that fish oil or omega-3 supplements do not promote heart health, including “multiple randomised trials” that tested the products against placebos and found no evidence of any heart-health benefits.
Since January, lawsuits have also been filed against the makers of Nordic Naturals, Nature’s Bounty and Spring Valley fish oil supplements, with the same two law firms filing all of the complaints except for the Spring Valley lawsuit, which is the most recent and states:
“The supplement industry, anecdotal evidence and earlier studies have often promoted these (heart-health) benefits. Once a narrative becomes deeply embedded in popular culture, it can be difficult to change, even when new evidence emerges.”
The lawsuits against Nordic Naturals, Nature’s Bounty and Spring Valley also cite potential health risks connected to the use of fish oil supplements that aren’t disclosed in the marketing, including the increased risk of atrial fibrillation.
Why don’t fish oil supplements work, according to these lawsuits?
The answer may have something to do with the manufacturing process. Several of the complaints link to a 2023 blog published by Harvard Medical School, which states:
“Many widely used fish oil supplements are produced through an industrial process that leaves the omega-3 fatty acids vulnerable to uncontrolled heat and oxygen,” said Preston Mason, a researcher who studies omega-3 fatty acids.
“This results in the oxidation of these highly unsaturated fatty acids, with a consequent loss of any biological benefit,” he says, adding that multiple laboratory tests on dozens of products have confirmed these findings.
The lawsuits do not explain how using fish oil supplements may lead to an increased risk of atrial fibrillation, given this “loss of any biological benefit.”
All of the lawsuits are pending.
Harvard Medical School article – The false promise of fish oil supplements (Open access)
Truth In Advertising article – Fish oil supplements marketed to support heart health (Open access)
See more from MedicalBrief archives:
Fish oil supplements may increase heart conditions risk – global study
Omega-3 fish oil supplements linked with lower CVD risk
Omega-3 supplementation linked with atrial fibrillation risk — Meta-analysis