For people at high risk of heart disease, taking omega-3 fatty acid supplements does not appear to reduce the risk of heart attacks or strokes, a new review study finds.
Previous research has found that people who regularly consume fish — which contain high levels of omega-3 fatty acids — have a lower risk of death from heart disease. But other studies that looked at whether taking omega-3 fatty acid supplements could lower the risk of heart disease or stroke have had mixed results. Some found that taking these supplements, sometimes called fish oil supplements, lowers the risk of death from heart disease, while other studies have found no benefit.
The new review analyzed data from 10 studies involving a total of nearly 78,000 people. These participants were randomly assigned to take daily doses of omega-3 fatty acid supplements or a placebo for at least one year. All of the participants either had heart disease or had experienced a stroke, or were at high risk for these conditions. Specifically, about two-thirds of the participants had heart disease, 30 percent had experienced a stroke and 37 percent had diabetes, which increases the risk of heart disease. [9 New Ways to Keep Your Heart Healthy]
The researchers found that, after about four years, participants who took omega-3 supplements were just as likely to experience a heart attack or stroke, or die from complications of heart disease, as those who didn't take the supplements.
The findings were the same regardless of participants' sex, history of heart disease, cholesterol levels or use of statin therapy to lower cholesterol levels.
The results are in contrast to guidelines from the American Heart Association, which recommends omega-3 fatty acid supplements for people with coronary heart disease or heart failure.
The new review "provides no support for current recommendations for the use of such supplements" for people with heart disease, the researchers concluded.
Still, the researchers noted that the participants in their review took about 1,000 milligrams of omega-3s a day, and more research is needed to assess whether higher doses of the supplements could be beneficial for heart disease patients.
The study was published online today (Jan. 31) in the journal JAMA Cardiology.
Original article on Live Science.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.