Topic Overview

Eating fish, at least 2 servings each week, is part of a heart-healthy diet.

Fish oil supplements can lower triglycerides. But doctors do not agree about whether these supplements can help protect your heart.

Fish and fish oil supplements do not lower cholesterol.

Fish

Eating fish may help lower your risk of coronary artery disease. As part of a heart-healthy diet, eat at least 2 servings of fish each week. Oily fish, which contain omega-3 fatty acids, are best for your heart. These fish include salmon, mackerel, lake trout, herring, and sardines.

The U.S. Food and Drug Administration (FDA) and the U.S. Environmental Protection Agency (EPA) recommend that women who may become pregnant, pregnant women, nursing mothers, and young children should not eat shark, swordfish, king mackerel, marlin, orange roughy, bigeye tuna, or tilefish from the Gulf of Mexico, because these fish have higher mercury concentrations. But for middle-aged and older people, the protection that fish gives the heart outweighs the risks of eating these fish. Eating a variety of fish may reduce the amount of mercury you eat.^{footnote 1}

Fish Oil

Why people may take fish oil

If you have severely high triglycerides, your doctor may recommend you take fish oil to try to prevent a problem with your pancreas called pancreatitis.

Sometimes people who don’t eat fish take fish oil supplements. Some doctors think fish oil might help the heart because it has the omega-3 fatty acids from oily fish. But other doctors don’t recommend these supplements to help the heart. That’s because research has not proved that fish oil is helpful for everyone.^{footnote 2}

If you have:^{footnote 2}

• Heart failure or have had a heart attack, fish oil supplements may have some benefit for you.
• Other heart problems, supplements have not been shown to help your heart.
• No heart problems, supplements have not been shown to help your heart.

What else to know about fish oil

If you take a medicine that prevents blood clots, called a blood thinner, do not take fish oil without talking to your doctor first. Taking fish oil at the same time as blood thinners may cause problems with bleeding.

Talk with your doctor first if you want to take more than 3 grams a day of a fish oil supplement. Doses this high can also increase the risk of bleeding.

Some people burp more often or have a fishy taste in their mouths when they take fish oil supplements.

What other foods have omega-3 fatty acids

If you don’t eat fish, you can get omega-3 fatty acids from foods such as omega-3 eggs, walnuts, flax seeds, and canola oil.

Most of these foods have a different kind of omega-3 fatty acid (called ALA) than the kinds of omega-3 fatty acids you get from eating oily fish (called DHA and EPA). There is not enough good research about whether ALA helps the heart.