You know that fish is good for you. Seafood of all varieties is high in protein and B vitamins and low in saturated fat, making it a smart substitute for red meat. It’s also the best source of heart- and brain-health-promoting omega-3 fatty acids DHA and EPA, which reduce inflammation, and it’s a helpful part of a healthy-weight diet. Still, while you may try to get in the recommended minimum of 8 ounces of seafood every week (that’s two servings), news reports about pollutants like mercury and concerns about environmental sustainability may leave you confused about how much and what kinds of fish you should be eating—or if you’re better off skipping it altogether.
Agencies ranging from the American Heart Association to the National Academy of Sciences to the World Health Organization agree that the benefits of seafood far outweigh any health risks, and we agree. However, “while many types of fish can be healthy choices,” says Marilyn Majchrzak, M.S., R.D.N., Canyon Ranch’s corporate food development director, “there are a few things to consider. As always, it helps to be an informed consumer, so you can make the most nutritious, safe and environmentally friendly decisions.”
Here, we answer some of the most common questions about seafood so you can confidently make it a part of your wellness plan.
Q: I’m concerned about mercury and other toxins in fish. How much seafood is safe?
A: This depends on your age and gender, but no matter what, you’ll need to choose wisely to limit your exposure to pollutants such as mercury, which accumulates in the flesh of fish, and polychlorinated biphenyls (PCBs), which build up in fish fat and skin.
For most of us, up to four servings of seafood per week is just fine. It’s best to avoid king mackerel, shark, swordfish, tilefish and blue fin tuna. These large, long-lived fish tend to contain more toxins than other species by the time they end up on your plate. Instead, choose a variety of mid-size to small fish, balancing fattier, omega-3-rich options like salmon, sardines, mackerel and oysters a couple of times per week with lower-fat options like canned light tuna, tilapia, cod, shrimp and sole the rest of the time. If you’re eating locally caught fish, be on alert for any advisories that may have been issued. And don’t worry about removing the skin from salmon and other fatty fish—if you’re choosing the cleanest possible selections and eating a variety of species, it’s not worth losing the valuable omega-3 fatty acids you’d be tossing out as well.
Developing fetuses are especially vulnerable to the harmful effects of mercury, so health agencies recommend that women who are pregnant or breastfeeding, or who plan to be, avoid eating large fish, especially those mentioned above. If you’re a woman in this category, you can safely eat up to 12 ounces (around three meals) of lower-mercury seafood like cod, salmon and shrimp per week.
Q: I’ve heard that eating certain types of fish is bad for the planet. How can I choose ones that aren’t?
A: Some species are threatened by overfishing, but choosing “sustainable” options whose numbers aren’t dwindling can help ensure that all fish will continue to be available in the future. Recommendations can change, but some wild species that are currently considered sustainable include Alaskan salmon; tilapia (from the U.S. and Ecuador); Pacific cod, Pacific halibut and Pacific sardines; and clams, mussels and oysters. Monterey Bay Aquarium Seafood Watch offers up-to-date printable guides and smartphone apps that can help you choose the best options in your geographic region. Another useful organization to refer to is the Marine Stewardship Council, an independent non-profit that certifies fisheries as being reputable and sustainable; look for the blue “certified sustainable seafood” label when you shop.
Q: Should I choose wild or farm-raised fish?
A: This decision has to do with both your health and the environment. We recommend seeking out wild salmon, which tends to be higher in omega-3s and lower in PCBs than its farmed counterparts, when you can. If you’re buying farmed fish, look for organic and/or sustainably raised seafood—depending on the conditions under which it was raised, it may be a comparable choice to wild varieties. Organic salmon that’s raised on uncontaminated feed will be lower in carcinogens, for example. Arctic char, striped bass (farmed in the U.S.), rainbow trout (farmed in the U.S.) and scallops are a few sustainable farm-raised choices, and Seafood Watch can direct you to others.
“You can’t be expected to trace the lineage of every fish you eat,” Majchrzak says. “But you can help raise awareness and demand for environmentally responsible fishing. Ask your grocer or restaurant owner about the origin of their fish, and then make the best choice possible. Just asking the question makes businesses aware that this matters to you—so it will matter more to them.”