A new review, published August 3 in the Journal of the American College of Cardiology, emphasizes the heart benefits of omega-3 fatty acids, found in oily fish. Unlike most dietary supplements, fish oils have proven effective at preventing and even treating heart disease in large controlled studies. But according to experts, many patients and doctors are not aware of how much research has been done in this area.
The review focused on 4 trials that tested the benefits of omega-3 in more than 40,000 patients. The studies looked at two major types of omega-3 fatty acids: EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Throughout the studies, these compounds (from diet or supplement pills) had numerous benefits, including:
- Preventing atrial fibrillation, heart failure, and sudden cardiac death
- Lowering the chances of dying in patients who have had a heart attack
- Improving survival in patients with heart failure
- Lowering triglyceride levels and cutting the risk of heart problems in patients with high cholesterol
- Preventing early harmful changes to the blood vessels (atherosclerosis)
Despite the proven benefits, the average American gets less than half the recommended daily intake of omega-3 fatty acids. The American Heart Association recommends that all women eat at least two meals a week that include a variety of fish (equivalent to about 500 milligrams of fish oil a day).
Fatty fish that are high in two kinds of omega-3 fatty acids (EPA and DHA) are best, including:
- lake trout
If you already have heart disease, you should consume about 1000 milligrams of omega-3s each day, preferably from fatty fish. Women who need to lower their triglyceride levels (a type of fat found in the blood) may need as much as 2000 to 4000 milligrams per day. It is hard to get this much fish oil through diet alone, so your doctor may recommended pill or liquid supplements that contain omega-3 fatty acids.
Omega-3 supplements should only be taken under a doctor's supervision, since they can increase the risk of bleeding in some women. Women who are pregnant, nursing, or planning to become pregnant should avoid eating fish that have high levels of mercury (such as shark, swordfish, king mackerel or tilefish).
Even if you are getting enough omega-3, an overall heart healthy diet (combined with regular exercise) is the most effective way to prevent heart disease: the benefits of omega-3 fatty acids can easily be outweighed if other aspects of your diet are unhealthy. See our Heart Healthy Diet article to learn more about how simple eating changes can improve your heart health.
Lavie CJ, Milani RV, Mehra MR, Ventura HO. Omega-3 polyunsaturated fatty acids and cardiovascular disease. J Am Coll Cardiol. 2009;54:585-94
Kris-Etherton PM, Harris WS, Appel LJ. Fish consumption, fish oil, omega-3 fatty acids, and cardiovascular disease. Circulation. 2002;106:2747-57