If you have heart disease, a study out yesterday in the Archives of Internal Medicine might make you think twice about taking fish-oil pills to prevent a second heart attack. But the American Heart Association is sticking to its longstanding recommendations—and so are we.
Researchers from South Korea looked at 14 prior clinical trials of omega-3 fatty acid supplements involving a total of 20,485 people with a history of cardiovascular disease. They found little evidence that omega-3 supplementation in those patients helped prevent heart attacks, sudden cardiac death, angina, congestive heart failure, or strokes. Given those findings, it's not surprising that they also didn't find that the pills helped people live longer.
But in an accompanying commentary, doctors from the Harvard School of Public Health and Brigham and Women's Hospital wrote that most of the studies the researchers looked at were very small and short-term, and that the current analysis left out two large clinical trials that might have tipped the balance in favor of fish oil pills.
The Harvard researchers recommended a diet high in fatty fish for the general public, including people with existing cardiovascular disease. "Fish not only provides omega-3 fatty acids but also may replace less healthy protein sources, such as red meat," they wrote. "Individuals who are unable or unwilling to eat fish or related products should consider increasing their consumption of plant-derived omega-3 fatty acid."
The American Heart Association has not changed its advice as a result of this new study. It recommends that consumers without documented coronary heart disease eat a variety of oily fish at least twice a week. And it says that people who have heart disease or very high triglyceride levels should talk with their doctor about taking fish-oil supplements.
Bottom line: Most people can get enough omega-3s by eating fatty fish, such as herring, salmon, sardines, and tilapia (which are also low in mercury), at least twice a week. But people who have coronary heart disease may require about a gram a day of those fatty acids, an amount that often requires taking a supplement in consultation with their physician. Also, check with a doctor before taking omega-3 pills because they can interact with some medications.
Efficacy of Omega-3 Fatty Acid Supplements (Eicosapentaenoic Acid and Docosahexaenoic Acid) in the Secondary Prevention of Cardiovascular Disease [Archives of Internal Medicine]
Omega-3 Fatty Acids and Secondary Prevention of Cardiovascular Disease--Is It Just a Fish Tale? [Archives of Internal Medicine]