Fish is so good for your heart that the American Heart Association recommends you eat it at least twice a week. Some studies show that those who regularly eat fish lower their risk of heart disease.

Fish is an excellent source of lean protein. Protein helps build and maintain your muscles, bones, blood, and other glands and organs. You also need protein to make hemoglobin, the part of red blood cells that carries oxygen throughout your body. Protein helps keep your immune system healthy, too.

Fish is a healthier source of protein than red meat. That’s because it doesn’t contain as much saturated fat, which can be harmful to your heart.

Fish and Omega-3 Fatty Acids

Fatty fish is a good source of fatty acids known as omega-3 fatty acids. Research has shown that omega-3 fatty acids can make it less likely that your heart will beat abnormally. Omega-3 fatty acids also are known to lower the amount of triglycerides, which are a type of fat, in your blood. Triglycerides build up in your blood vessels and cause dangerous blockages. Some research suggests that omega-3s also may help lower blood pressure.

Which Fish to Eat 

These fish have high amounts of two kinds of omega-3 fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA):

  • Salmon
  • Albacore tuna
  • Mackerel
  • Herring
  • Trout
  • Sardines
  • Shellfish

A serving is 3.5 ounces. That’s about three-fourths of a cup of flaked fish. It’s best to grill, sauté, bake or steam fish. Don’t fry it. Also, avoid sauces that are high in fats. Try a sprinkle of olive oil instead of a sauce.You also can get omega-3s by taking fish oil supplements. But, the American Heart Association says it’s better to go to the source and eat fish if you can.

Beware of Fish Contaminants 

Some fish live in polluted waters and may be contaminated by mercury and PCBs (polychlorinated biphenyls). If you eat too much contaminated fish, that can offset the heart-healthy benefits. To avoid this, eat a variety of fish. And, check where the fish came from, whenever possible.

Written by Beth W. Orenstein, this story originally appeared on healthguides.healthgrades.com