Dutifully down your omega-3 fatty-acid supplement every day? You may want to take a closer look at your capsules.

Recent tests done by ConsumerLab.com found that 31 percent of the omega-3 fatty acid supplements tested failed to live up to their label claims. What researchers found could mean that pill-poppers’ efforts to channel the supplement’s benefits–decreasing the risk of heart disease, cancer, arthritis, macular degeneration, and more–have been useless, and even dangerous.

Labels That Lied
Of the thirty-five kinds of omega-3 fatty acid supplements researchers examined, including those containing fish oil, krill oil, calamari oil, cod liver oil, and algae oil,  several products missed the mark on how much of the healthy fatty acids the supplements actually contained, and some even posed health hazards.

• Four packed less fatty acids than than their labels claimed.

• Three had up to 267 percent more fatty acids than their labels claimed.

• Two exceeded safe levels of polychlorinated biphenyl (PCB), a chemical used in coolants and insulating fluids that’s been banned in the U.S. since 1979, but still contaminates waterways throughout the country. “Every fish oil supplement contains trace levels of PCBs, but two of those we tested exceeded levels safe for human consumption,” says Tod Cooperman, M.D., president of ConsumerLab.com. (The EPA considers PCBs a potential carcinogen and research shows it may also harm the immune and reproductive systems.)

• One tablet’s enteric-coating didn’t work, which means that the special coating meant to release the oil in the intestine rather than the stomach (to reduce the likelihood of a fishy aftertaste or burp) spilled the oil too early in the digestive system.

• One was spoiled. Although there aren’t any serious health effects due to spoilage, it may cause burping and other G.I. issues, Dr. Cooperman says.

Now What?
Since setting up your own testing lab in your kitchen isn’t an option and because the FDA doesn’t regulate supplements, it’s difficult to know whether your go-to pills would pass the test. Fortunately, there are several steps you can take to keep yourself safe.

Consider your needs. “If you regularly eat fish at least twice a week you don’t need to take omega-3 supplements because you’re likely already getting enough,” Dr. Cooperman says. (Check out Women’s Health’s healthiest fish and seafood rankings.)

Store your supplements safely. “Refrigerate fish oil supplements to prolong their life and reduce the risk of spoilage,” he says.

Pop test-passing pills. To find out which pills passed the test, check out ConsumerLab.com’s most recent review. One finding that’s easy to swallow: According to the report, there are high-quality fish oil supplements that aced every test for as little as $ 0.01 per 100 mg of fatty acids.

More from WH:
The Best Food Sources of Omega-3 Fatty Acids
How Much Fat Is Healthy?
10 Snacks that Fight Fat
Supplement Directory

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