Choose Your Fish Wisely

There are a lot of good reasons to eat seafood—recent studies have linked the omega-3 fatty acids found in deep water fish to a lower risk of heart disease; fish are a good source of protein, and early studies hint that pregnant women who eat fish or take fish oil supplements are more likely to carry babies to full term, and to enhance their babies’ cognitive development.

But eating more fish isn’t easy. The healthy bonus that comes from fish, it seems, has a price. The same fats that make fish so good for the heart and the body also attract dangerous toxins, from dioxins to polychlorinated biphenyls (PCBs), the man-made byproducts of the electrical industry. (While PCBs have not been created since the 1970s, trace amounts still linger in waters.) In addition, the lean muscle of the ocean’s biggest and most powerful swimmers can become sinkholes for methylmercury, a potentially brain- and liver-damaging metal formed when salts are processed by certain anaerobic bacteria. Is it safe to eat fish at all? Are the benefits of eating fish enough to outweigh these risks? How much fish is safe to eat? Which kinds of fish and seafood have the most omega-3 fatty acids and the lowest levels of contaminants?