What are Omega-3 Fatty Acids

Contributors: Esther Ellis, MS, RDN, LDN
What are Omega-3 Fatty Acids

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Research shows that eating two 4-ounce servings of seafood per week may reduce the risk of heart disease and related deaths. Many health professionals attribute this potentially life-saving quality of seafood to the presence of omega-3 essential fatty acids. And, omega-3s are not limited to fish and seafood. They are also found in some vegetable oils, nuts, seeds and soy foods.

Fish contain two important omega-3 fatty acids: EPA (eicosapetaenoic acid) and DHA (docosahexaeonic acid). Research suggests people who eat fatty fish and other seafood as part of a healthy dietary pattern have lower risk of heart problems and lower risks of chronic disease. This has been seen in individuals with and without a history of heart disease, though evidence is stronger for the benefits of omega-3 fatty acids in people with a history of heart disease. For instance, if you have high blood triglycerides, consuming omega-3 fatty acids may help lower your levels.

Plant-Based Omega-3s

Some plants also contain an omega-3 fatty acid known as ALA (alpha-linolenic acid). You can find it in various oils, nuts, seeds, beans and other sources. Here are tips for getting more plant-based omega-3s:

  • Include vegetable oils that contain omega-3 fatty acids, such as flaxseed oil, walnut oil, canola oil or soybean oil.
  • Add hemp hearts or ground flaxseed to cereals, yogurt and salads. The body isn't able to break down whole flaxseed effectively but grinding them before using helps with absorption.
  • Substitute ground flaxseed for butter or oil when baking. Use 3 tablespoons of ground flaxseed instead of 1 tablespoon of oil.
  • Snack on edamame or walnuts for a snack rich in omega-3 fatty acids.

Omega-3 Supplements

Omega-3 supplements may be beneficial in combating heart disease though recent studies have challenged if taking supplements is as effective as consuming food sources. Scientific evidence describing the advantage of omega-3 supplements on heart disease risk for people who don't actually have heart disease is also limited. Consult a health professional to determine if you would benefit from an omega-3 supplement.

Too Much Omega-3?

Given the fact that many of our foods are fortified with omega-3 fatty acids, it is possible to get excess amounts of it if you take additional supplements. The U.S. Food and Drug Administration advises consuming no more than 3 grams of omega-3 fatty acids per day (2 grams a day from supplements). Taking too much may cause uncomfortable gastrointestinal symptoms. And, although small, there is a risk of increased bleeding possible when people who take anti-platelet agents or anticoagulants also take high doses of omega-3 fatty acids.

The omega-3 fatty acid content of fish varies. Higher amounts are typically found from sources such as herring, salmon, sardines and trout. Mackerel is also a rich source of omega-3 fatty acids, however, one variety known as king mackerel is also high in mercury and the FDA advises women who are pregnant, nursing mothers and young children to avoid this fish. Atlantic mackerel and Spanish mackerel are both lower mercury alternatives.

In summary, remember to feast on fish at least twice a week and regularly include omega-3-rich plant sources, such as flaxseeds, chia seeds and walnuts, in your diet.

Finally, ask your doctor or a registered dietitian nutritionist to determine if an omega-3 fatty acid supplement would be helpful for you. Omega-3 fatty acid supplements should not be taken without a physician's supervision.

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