While health experts recommend eating more fish and less red meat, concerns about mercury levels, sustainability, and cooking methods may prevent you from making this dietary change.

Concerns about mercury

Exposure to mercury in contaminated fish and seafood can lead to neurological disorders and cognitive issues, particularly in fetuses and young children. Women who are pregnant or nursing should also limit their exposure to mercury. Chronic exposure in adults can contribute to memory loss, tremors, and immune system suppression.

Large fish tend to have higher mercury levels than small fish because they feed on smaller fish. Health agencies recommend that people in high-risk groups avoid shark, swordfish, king mackerel, and tilefish. Up to 12 ounces of low-mercury fish and shellfish, such as shrimp, canned light tuna, salmon, and catfish, can be enjoyed each week.

Making sustainable choices

Fishing and farming methods influence the fish population and the ecosystems important for healthy marine life. The popularity of fish as a health food has put some species at risk for overfishing, which has decreased some populations to dangerously low levels. As a result, many fish are now farm-raised. While farm-raised fish can be a healthy choice, some are raised in unhealthy environments, spreading disease and parasites.

All of these factors make choosing a truly healthy fish difficult, but there are resources to help. The Monterey Bay Aquarium Seafood Watch program provides a guide for selecting fish based on human and environmental health as well as the health of the fish species. Types of fish are divided into “Best Choices,” “Good Alternatives,” and “Avoid.” This guide is updated every six months and is a reliable resource for making healthy, sustainable fish choices. (See the Seafood Watch Seafood Recommendations.)

Best cooking methods

Fish and seafood are full of lean protein, but when battered and deep fried, the added saturated fat and sodium quickly turn a healthy choice into an unhealthy meal. There are plenty of flavorful ways to prepare fish without canceling out the nutritional benefits. Bake or broil fish fillets with fresh herbs and finish with a squeeze of lemon or lime before serving. Steam whole fish or fish fillets with fresh greens and add spices like curry or chili powder. Marinate large fish fillets in olive oil, herbs, and citrus zest for a few minutes and grill over high heat. You also don’t have to give up breaded, crispy fish. Use cornmeal, whole wheat bread crumbs, or almond meal to coat fish fillets and then bake or skillet fry in a small amount of olive, avocado, or virgin coconut oil.

Sources

• The World Health Organization — Mercury Fact Sheet
• Natural Resources Defense Council — Mercury Contamination in Fish

Lori Rice, M.S., is a nutritional scientist and author with a passion for healthy cooking, exercise physiology, and food photography.