In the child’s card game, you draw until you get the right card. In real life, figuring out fish is not so easy.
Selecting the best fish to eat often resembles this random game of chance. Eat fish regularly and you reduce your risk for heart disease, cancer, Alzheimer’s, stroke, diabetes, and inflammatory disease such as rheumatoid arthritis. Eat fish regularly and you also increase your exposure to mercury, environmental contaminants, and microbes.
Public health experts are urging us to eat more fish. But, recent A.C. Nielsen data showed 11 million low-income Americans —many of whom are at high risk for obesity, diabetes, and heart disease—have stopped eating canned tuna because of the caution about mercury. Yet canned tuna has no equal when it comes to affordable, lean protein, rich in heart-healthy omega-3 fatty acids.
So let’s cut to the chase. We need to eat more fish. How much? How often? And, which fish should we eat?
Let’s start with tuna. There is no question that all canned tuna contains some mercury. Mercury is a naturally occurring element in nature found in trace amounts in many foods. The key is to keep the exposure low. Light tuna has less mercury than albacore, which comes from larger fish. Chunk-light contains even less than solid-light. Consumer’s Union recommends adults limit intake to no more than 3 cans of chunk-light or 1 can of solid-light or white albacore per week.
You should know: You can go to GotMercury.org and enter the type and amount of fish you will be eating plus your weight, and the site will calculate how much mercury you will eat.
To make informed decisions about choosing fish, we need to weigh the risks and benefits. Pregnant women, women who are trying to become pregnant, and children under 12 should avoid large predatory fish—swordfish, shark, king mackerel, tilefish and whale—and limit their intake of white tuna. But, this is not a concern for men. It’s hard to make a list of “good fish” and “bad fish” because seafood supplies change constantly and the list could become obsolete quickly. The benefits and risks of broad categories of seafood do remain relatively consistent.
- Lean fish such as flounder are excellent sources of protein, low in saturated fat and cholesterol, and offer moderate amounts of omega-3 fats. The levels of mercury are higher in larger fish and lower in smaller fish and farm-raised fish. Eat fish lower on the food chain.
- Fatty fish such as salmon are good sources of protein and offer the highest amounts of omega-3 fatty acids, but they also contain higher levels of saturated fat and cholesterol, and may have higher levels of pollutants like dioxin and PCBs. Their mercury level is lower than that in lean fish.
- Shellfish and crustaceans (lobster, crab) are high in protein, low in saturated fat. But some, like shrimp and mussels, contain a fair amount of cholesterol. If eaten raw, there is a risk of microbial infection. Children, pregnant women, and older adults should stick with cooked.
- The level of environmental contaminants in all types of seafood is low enough not to pose a health risk. For species or bodies of water that have levels high enough to pose a health risk, regional and local sources issue alerts.
You should know: More nutrients are retained in fish that is baked or broiled rather than processed or fried.
Now let’s look at the risks and benefits of eating fish by sex and age.
Women of childbearing age, those who are pregnant or breastfeeding, and kids under 12:
- Will benefit from the nutrients found in seafood
- Should limit consumption of white (albacore) tuna to 6 ounces a week
- Should avoid large predatory fish
- Should eat 2 servings of fish a week
Teenagers, adult men and women who do not plan on a pregnancy:
- May reduce their future risk of heart disease by eating fish regularly
- If eating more than 2 servings of fish a week, choose those with lower levels of mercury or contaminants
- If they are at known risk for heart disease, select seafood with higher amounts of heart-healthy omega-3 fatty acids—salmon, shrimp, pollack, cod, light tuna, and catfish
You should know: By law, fish and shellfish must be labeled for country of origin and method of production (wild or farm-raised).