Health Information Library

Omega-3s: How to catch some healthy benefits

Salmon, avocados, oil, nuts and seeds on a wooden table.

Learn how fish and other foods rich in omega-3 fatty acids may help protect your health—plus tips on the best ways to get them.

What do salmon, walnuts, flaxseed and canola oil have in common? They're terrific sources of omega-3 fatty acids. And that's worth taking note of.

Foods rich in omega-3 fatty acids may offer a variety of good-for-you benefits. Omega-3s are a type of unsaturated fat found in fatty fish and some plant-based foods. And they've been linked to health benefits such as:

Heart health. Scientists have found that people who regularly eat seafood have a reduced risk of dying from heart disease. That may be, in part, due to the omega-3s and, in part, due to lifestyle factors such as eating seafood in place of less healthy foods. The American Heart Association (AHA) reports that omega-3s may help protect against heart disease and stroke by:

  • Lowering high levels of triglycerides (a type of fat found in the blood).
  • Slowing the growth of plaque that clogs arteries.
  • Slightly lowering blood pressure.

Arthritis relief. Because omega-3s from fish can inhibit inflammation, they may help ease the symptoms of rheumatoid arthritis, according to the Arthritis Foundation. People who eat fish regularly are even less likely to develop rheumatoid arthritis.

Prenatal health. In pregnant women, omega-3s found in fish may help reduce the risk of early delivery and help a baby's brain and eyes develop, notes the March of Dimes.

Brain health. There's some evidence that omega-3s may help reduce the risk of cognitive decline and dementia. However, omega-3s have not been shown to help prevent or treat Alzheimer's disease.

Good sources of omega-3s

The best way to get a wholesome mix of nutrients, including omega-3s, is to eat a variety of healthy foods. Besides fish, omega-3s are found in some vegetable oils, nuts, seeds and beans. So it's not hard to fit them into your diet. For instance, try these tips from the AHA and the Academy of Nutrition and Dietetics:

  • Eat fish at least twice a week. Salmon, lake trout, mackerel, herring, sardines and albacore tuna are high in omega-3s. Check out these ideas for fitting more fish into your diet.
  • Add walnuts to salads and cereals.
  • When cooking or baking, choose oils such as soybean and canola instead of solid fats like butter or margarine.
  • Add ground flaxseed to cereal, yogurt, bread, baked dishes or casseroles.
  • At the grocery store, look for products like eggs, milk or orange juice fortified with omega-3s.

A word about mercury

Some types of fish have a lot of mercury, a metal that can be harmful in high amounts. For most people, the benefits of fish far outweigh any risks, but some people need to use caution.

If you are pregnant or are nursing, the U.S. Food and Drug Administration and the U.S. Environmental Protection Agency recommend that you:

  • Eat 8 to 12 ounces (two to three servings) of fish low in mercury each week.
  • Limit albacore tuna to no more than 6 ounces a week.
  • Avoid eating fish high in mercury, such as shark, swordfish, king mackerel and tilefish. (It's unlikely you'll encounter these fish, since most fish sold in stores are low in mercury.)

For most people, eating a variety of fish will help ensure that your exposure to mercury stays low while still taking advantage of the healthy benefits fish offer.

What about supplements?

Omega-3 fatty acids are also sold as dietary supplements. But research does not show that they protect against heart disease. And if you only take a fish-oil capsule, you won't get all the other good nutrients fish provide.

High doses of omega-3s may increase the risk of bleeding in some people. So talk with your doctor first if you're thinking about taking an omega-3 supplement.

Reviewed 12/12/2023

go