Features August 2011 Issue

Omega-3 Fatty Acids Offer Heart Protection in Multiple Ways

These healthy essential fats provide benefits whether consumed as supplements or from dietary sources.

If you take fish oil supplements or you make baked or broiled fish part of your regular diet, you’re doing a great favor for your heart. Two recent studies have underscored the growing body of research linking omega-3 fatty acids to improved cardiovascular health. Omega-3 fatty acids are called essential fats because the body cannot produce them; they must be consumed from foods.

In a study published in the May issue of Arteriosclerosis, Thrombosis and Vascular Biology: Journal of the American Heart Association, researchers found that taking omega-3 supplements along with two blood-thinning drugs helped change the blood-clotting process in patients with stents in their coronary arteries. The result was that clots that did form in those patients were more easily destroyed than clots that formed in similar patients who only took the two blood thinners, which were aspirin and clopidogrel.

In a separate study, published in the May issue of Circulation: Heart Failure, the risk of developing heart failure was lower for postmenopausal women who frequently ate baked or broiled fish, compared to women who ate little or no fish. Women who ate fried fish experienced a higher risk of developing heart failure, compared to those who ate less than one serving of fish per month. Fish is one of the best dietary sources of omega-3s.

Cleveland Clinic registered dietitian Andrea Dunn, RD, LD, CDE, says that omega-3s help the heart in numerous ways. They act as a natural anticoagulant by altering the ability of platelets in the blood to clump together, and they help keep the lining of the arteries smooth by inhibiting the growth of plaque. Omega-3s also help lower triglyceride levels in the body, which helps lower the risk of heart disease.

"Because omega-3 fatty acids lower triglyceride levels, they also help increase HDL ("good") cholesterol, which protects against the development of heart disease," Dunn says. "Several studies have examined the effect of omega-3 fatty acids on blood pressure, and those who eat fish tend to have a lower incidence of high blood pressure."

Omega-3s also appear to have anti-inflammatory properties, which have many benefits, including the inhibition of atherosclerosis.

Omega-3 Sources

Omega-3 supplements, commonly sold as fish oil, are often recommended to individuals who don’t get omega-3s in their diet. For a significant reduction in triglycerides, though, you may have to take as many as eight to 15 tablets daily. Health experts tend to agree that getting those essential fatty acids from dietary sources is the preferred way to go. Dunn says that coldwater fish, such as salmon, mackerel, tuna and sardines, all have high amounts of omega-3s. She adds that the American Heart Association recommends eating two servings of fish—about six ounces—each week.

And if you don’t like fish, you can get a form of omega-3 called alpha-linoleic acid (ALA) from plants. ALA breaks down minimally into the two types of omega-3s found in fish: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). While ALA doesn’t have as strong a heart health benefit as EPA and DHA, it’s still a viable source of omega 3s. If you take fish oil supplements, be sure to read the labels to maximize your EPA and DHA intake, since a bottle of fish oil may have 1,000-mg tablets, but only 360 mg of that are EPA and DHA and the rest is filler.

Dunn says that good ALA sources include flaxseeds, flaxseed oil, walnuts, soy foods and canola oil. "Flaxseeds must be ground up to get the benefit of the ALA," she explains. "Humans will pass the seeds whole and not benefit from these good fats if they’re not ground up. And be aware that oils can be high in calories, too."

She adds that algae and algae oil, which breaks down to DHA in the body, are good ALA sources, and that many omega-3 fortified foods use algae oil.

Fried Fish Dangers

The fish study that favored baked and broiled fish over fried noted that frying meat, poultry or seafood can significantly increase the calorie content of food, since fried foods absorb the fat that they are cooked in. "Fried fish and other meats are often breaded, which just adds to the calories," Dunn says.

She also notes that frying can create carcinogenic compounds called heterocyclic amines (HCAs), which can damage DNA and contribute to development of cancer, particularly in the colon and stomach.