New guidelines focus on fish oil, omega-3 fatty acids

FDA Consumer, Jan-Feb, 2003

Healthy people should eat omega-3 fatty acids from fish and plant sources to protect their hearts, according to updated recommendations by the American Heart Association.

"Omega-3 fatty acids are not just good fats; they affect heart health in positive ways," says Penny Kris-Etherton, Ph.D., R.D., lead author of a report published in the Nov. 18, 2002, issue of Circulation: Journal of the American Heart Association.

Omega-3 fatty acids make the blood less likely to form clots that cause heart attack, and they protect against irregular heartbeats that cause sudden cardiac death, the report says.

Kris-Etherton and colleagues examined the health benefits of omega-3 fatty acids in the context of cardiovascular disease (CVD) risk reduction and considered the recent Environmental Protection Agency and Food and Drug Administration guidance about the presence of contaminants in certain species of fish.

Since 2000, the American Heart Association's dietary guidelines have recommended that healthy adults eat at least two servings of fish per week, particularly fish such as mackerel, lake trout, herring, sardines, albacore tuna and salmon. These fish contain two omega-3 fatty acids--eicosapentaenoic and docosahexaenoic acids (EPA and DHA). A third kind, alpha-linolenic acid, is less potent and comes from plants, including tofu and other forms of soybeans, and nuts and seeds and their oils, including canola, walnut and flaxseed oils.

People who have elevated triglycerides may need two grams to four grams of EPA and DHA per day provided as a supplement, according to the new guidelines. Those taking more than three grams of omega-3 fatty acids from supplements should do so only under a physician's care. The FDA has noted that high intakes could cause excessive bleeding in some people.

The mechanisms responsible for omega-3 fatty acids' reduction of CVD risk are still being studied, and include decreases in triglyceride levels and blood clots, lower risk of sudden death, improved arterial health, and lower blood pressure.