Good Things Come in [Omega] Threes

By Rachel Johnson, Ph.D, M.P.H., R.D., January/February 2007

"Fish fats" prove a powerful way to protect the heart.

Plant foods like flaxseed, soybeans, canola and walnuts are good sources of alpha-linolenic acid (ALA), another omega-3 with its own heart benefits. A small amount of ALA is also converted to EPA and DHA in the body, “but at a very slow rate,” says William Connor, M.D., a longtime friend of mine and a professor at Oregon Health & Science University who has studied fish and fish oils for more than 30 years. If it’s heart-health effects you’re after, he emphasizes, “what you want are EPA and DHA, from fish or fish-oil supplements.”

But omega-3s are usually lacking in our diets, vastly outnumbered by omega-6 fatty acids common to processed foods made with vegetable oils including safflower and cottonseed. Omega-6s tend to promote inflammation, while omega-3s reduce it. Many experts believe our American diets tilt too much toward omega-6s, and that the best way to restore balance is to boost our intake of omega-3s from any source.

So I’m doing my darnedest to eat more omega-3s. I aim to serve a fatty fish like salmon twice a week, and consider the seafood dishes first in restaurants. I sprinkle walnuts on my salads and make dressings with canola oil.

As ever, moderation is key. Very high intakes of fish-based omega-3s (over 3,000 mg/day) can raise the risk of excessive bleeding or even hemorrhagic stroke. And, like any fat source, omega-3s are still calorie-rich. So focus on substituting (not adding) omega-3s for other fats you eat. After all, the most important thing you can do for your heart is to be at a healthy weight. Without that, keeping your heart healthy is just a fishing expedition.

—Rachel Johnson, EatingWell’s senior nutrition advisor, is dean of the University of Vermont College of Agriculture & Life Sciences.

Get a full year of EatingWell magazine.
World Wide Web Health Award Winner Web Award Winner World Wide Web Health Award Winner Interactive Media Award Winner