The wildly popular supplement — which is on track to reach an estimated $2.4 billion in worldwide sales by 2030 — might not provide any health benefit, according to scientists.
But that hasn’t stopped manufacturers from making outrageous claims on the packaging for fish oil supplements.
A recent study from the University of Texas Southwestern Medical Center in Dallas, Texas, found the labels on fish oil supplements make health claims that are completely unsubstantiated by any research.
“Based on what I’ve seen personally in the grocery store and pharmacy, I was not surprised to find such high rates of health claims on fish oil supplements,” study co-author Joanna Assadourian.
“What was surprising, though, was just how broad the types of claims being made were ― from heart and brain health to joint health, eye health and immune function,” Assadourian added.
There are two types of health claims made on supplement packages: A qualified health claim mentions a supplement’s potential to treat or prevent disease, and must be approved by the Food and Drug Administration.
Claims can describe how a supplement supports the functioning of the body (e.g., “supports immune function”) but must stop short of saying it prevents, treats or cures any disease.
Out of 2,819 fish oil supplements that the researchers studied, 74% made at least one health claim. Of these, only 19% used an FDA-approved qualified health claim, while the others made broad or unproven claims about how the ingredients are structured or function in the body.
In addition to heart health claims, many fish oil supplements say that they benefit other organ systems, such as brain, mental health, joint health or eye health ― despite absolutely no data from clinical trials to support those claims.
“The labels can be very misleading to the general public,” said Dr. JoAnn E. Manson, chief of the Division of Preventive Medicine at Brigham and Women’s Hospital in Boston.
“People are confronted with a dizzying array of dietary supplements, many of which include structure/function claims that require minimal, if any, evidence of efficacy,” she added.
“The enthusiasm for these supplements outpaces the evidence from rigorous randomized clinical trials.”
Roughly 20% of people over the age of 60 take fish oil supplements.
Studies have shown that the omega-3 fatty acids found in fish such as salmon and mackerel provide health benefits, but the same has not been true for omega-3 fatty acids that come from supplement capsules.
In a 2018 study of more than 15,000 people with diabetes, the risk of a serious cardiovascular event was no different between people taking an omega-3 supplement and people who were not.
A 2019 study with more than 25,000 participants found that fish oil supplements did nothing to reduce the risk of a major cardiovascular event (such as a heart attack or stroke) or getting cancer.
Instead of relying on supplements, most nutritionists recommend that people get their omega-3 and other fatty acids from dietary sources.
Sources of healthy fatty acids, according to the National Institutes of Health, include:
- Cold-water fish such as salmon, herring, tuna, sardines and mackerel
- Flaxseed, walnut, soybean, canola and olive oils
- Chia seeds
- Walnuts
- Olives
- Eggs
The authors of the latest study, published in JAMA Cardiology, found significant gaps in current supplement labeling laws.
