Have a Daily Dose of Omega-3

What do my dog, horse and husband all have in common -- besides me? All three start the day with a sprinkle of omega-3 in their breakfast bowls. Maybe you do, too.

The animals are sublimely unaware that they consume it (in the form of flaxseed) or why (because of evidence it may ease arthritic aches and pains and put a shine on their coats). But my husband is on to the health benefits. He has a daily, 2-tablespoon, 3,500-milligram dose of ground flaxseed on his granola. He says it has a "nutty" taste.

Cardiologists praise omega-3 fatty acids. Found in fatty fish like salmon and mackerel, as well as in flaxseed, canola oil and walnuts, they protect the heart against inflammation that can result in blocked arteries and can prevent irregular heartbeats that can lead to a sudden heart attack. And there's growing evidence that these polyunsaturated fats avert strokes, reduce inflammation and joint pain from arthritis, and promote brain and vision development in infants. Statistics even link omega-3s to broader health benefits -- for example, they may ward off complications from diabetes. They're being used to treat depression and Alzheimer's disease. Better skin, stronger fingernails and more energy are also possible perks.

Unfortunately, there are data to suggest that farmed salmon, the fish most of us trust as a great source of omega-3s, can pose a health risk. Farmed salmon are raised on fish oil pellets derived from local fish, which are often contaminated with cancer-causing PCBs. One study in the November 2005 issue of the Journal of Nutrition reports that contaminant levels in farmed salmon from certain regions increase the risk of cancer enough to outweigh benefits.

The study concluded that as a whole, risks exceed benefits for farmed Atlantic salmon. Farmed salmon from South America, specifically Chile, had the lowest level of pollutants, followed by North America. Europe had the highest level, according to David Carpenter, coauthor of the study and director of the Institute for Health and the Environment at the University at Albany's School of Public Health (Albany, New York). Pacific wild salmon also have contaminants, but at a low enough level that the benefits outweigh the risks.