There's no question that eating more fatty fish, such as salmon, is good for your health. Rich in omega-3 fatty acids, these fish lower bad cholesterol and slightly raise good cholesterol. That much is easy. It's choosing the right salmon that can get a little confusing. Farm-raised or wild? Atlantic or Pacific?

There are three kinds of salmon commonly found in U.S. fish markets: Alaska, Pacific, and Atlantic. In terms of taste, Alaska and Pacific have a stronger, fishier flavor than Atlantic, which tends to be mild in both flavor and color. Alaska salmon is not raised on farms, and neither is most Pacific salmon. That makes them pricey. Wild Atlantic salmon is practically extinct. In the past 30 years, populations in North America have declined from 1.5 million to 400,000. But fresh, farm-raised Atlantic salmon is cheap and widely available. When you open a menu in a restaurant in the United States, chances are farm-raised Atlantic salmon is what's listed.

Price and availability aside, there's another issue clouding the waters. The National Audubon Society, the Environmental Defense Fund, and California's Monterey Bay Aquarium oppose farm-raised salmon and claim it is one of the main causes of the dwindling wild-Atlantic-salmon population. Salmon-farm escapees, they say, breed with native salmon, infecting them with diseases, weakening the gene pool, and lowering survival rates — not to mention that the water surrounding salmon farms is heavily polluted with large quantities of uneaten food, pesticide residue, and general waste.

The upshot of all this? When you have the option, choose Alaska salmon. Its harvest is regulated, and stocks are plentiful.