Topic Overview

Eating fish, at least 2 servings each week, is part of a heart-healthy diet. But fish and fish oil supplements do not lower cholesterol.

Some people take fish oil supplements to help lower triglycerides. Fish oil supplements can lower triglycerides.

Fish

Eating fish may help lower your risk of heart 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, or tilefish, 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.^{1, 2}

Fish oil

Some people with high triglycerides may take a prescription omega-3 fatty acids medicine (such as Lovaza or Vascepa). This medicine is a highly concentrated form of omega-3 fatty acids, which are found in fish oil. This medicine is used along with diet and lifestyle changes for high triglycerides.

Fish oil capsules that you can buy without a prescription can have significant side effects. Because of these side effects, most doctors recommend eating 2 or 3 servings of fish a week rather than taking fish oil capsules. The side effects of fish oil capsules include:

• Large amounts of omega-3 fatty acids (the main type of fatty acid in fish oil) can greatly reduce the ability of the blood to clot normally.
• Fish oil can cause nausea, diarrhea, belching, and a fishy taste in the mouth.
• Taking large amounts of fish oil greatly increases the number of calories in the diet. Some suggested doses add more than 200 calories a day.