The government’s Dietary Guidelines for Americans recommend that adults eat about 8 ounces of fish (or shellfish) a week for the “total package of nutrients” it provides. That’s in line with recommendations from the American Heart Association. In particular, fatty fish like salmon is advised because of its omega-3 fats. Moreover, the Dietary Guidelines advise women who are pregnant or breastfeeding to eat 8 to 12 ounces of fish a week because many of these nutrients are important for fetuses and breastfed infants.
The key is that the fish should be low in mercury, a contaminant that can harm the brain and nervous system, especially during development. This complicates shopping for fish.
Now the FDA and EPA have released user-friendly advice to help pregnant women, women who might become pregnant, and parents of young children make healthy and safe fish choices. The agencies recommend that such women eat two or three 4-ounce servings (before cooking) a week of a variety of fish that are lower in mercury. Previously they merely set a 12-ounce maximum intake for these groups; they have now added a minimum intake because many pregnant women eat little or no fish. They note that other adults can also follow this advice.
Keep in mind that people who don’t like fish or are vegetarian can, with a little planning, get its key nutrients from other healthy foods, except for the long-chain omega-3 fats. As the FDA and EPA say, you can have a healthy baby even if you don’t eat fish. For everyone, the total dietary pattern is most important.
Making the best choices
The new advice, presented in a color-coded chart, lists 55 types of fish that are either “best” or “good” choices, as well as seven large fish that should be avoided because of potentially high mercury levels. You can eat “best” choices two or three times a week or a “good” choice once a week. You should vary your intake. The web page also discusses serving sizes, children’s intakes, contaminants in fish, different types of tuna, and recreationally caught fish.
- Best choices (2 to 3 servings a week): Anchovies, black sea bass, butterfish, catfish, clams, cod, crab, crawfish, croaker (Atlantic), flounder, haddock, hake, herring, lobster, mullet, oyster, mackerel (Atlantic or Pacific chub), perch, pickerel, plaice, pollock, salmon, sardines, scallops, shad, shrimp, skate, smelt, sole, squid, tilapia, trout, tuna (canned light), whitefish, whiting.
- Good choices (only once a week): Bluefish, buffalofish, carp, Chilean sea bass, croaker (Pacific), grouper, halibut, mahi mahi, monkfish, rockfish, sablefish, sheepshead, snapper, Spanish mackerel, striped bass, tilefish (Atlantic), tuna (albacore or yellowfin, canned or fresh), weakfish.
- Avoid (because of mercury): Bigeye tuna, king mackerel, marlin, orange roughy, shark, swordfish, tilefish (Gulf of Mexico).
This advice does not take into consideration fishery sustainability issues—for guidance, go to fishwatch.gov or seafoodwatch.org. In addition, how fish are caught is important. For instance, tuna that are pole- or troll-caught tend to be smaller and thus have less mercury. And recreationally caught fish may have higher levels of contaminants; consult state advisories to find out how often you can safely eat such fish.
Also see How Safe Is Your Imported Seafood?