Every day, millions of Americans take fish oil supplements to help improve or protect heart health. Unfortunately, despite the dietary supplement industry’s marketing efforts, the New York Times points out that there’s not a lot of evidence fish oil supplements lower the risk of heart attack or stroke. As the Times notes, sales of fish oil have increased as more research has been published showing fish oil has no effect on cardiovascular function.

The increase in fish oil supplement use may be a response to overblown fears of mercury in fish—fears the U.S. Food and Drug Administration has tried to squash with its recent bulletin urging Americans, especially women of childbearing age, to eat more fish. Eating fish provides consumers with many more nutrients than those contained in fish oil supplements.

Fish oil may not be totally useless—it’s being studied for treatment of cancer, Alzheimer’s, and depression. But if you’re looking for heart benefits from fish oil, you may want to stop wasting your money and communicate with your doctor on other dietary and lifestyle changes you can make to improve your cardiovascular health.