[Updated April 30, 2018]
Q: I live in a retirement home and eat fish every day: salmon on Monday, Wednesday, and Friday and tuna the other days. Is this good for me or should I cut down?
Grace Ling, Dietetic Intern, Tufts Medical Center, Graduate Student at the Friedman School of Nutrition Science and Policy, says:
A:“The 2015-2020 Dietary Guidelines for Americans recommend that adults eat 8 ounces or more of seafood per week (less for young children). That means two (or more) 4-ounce servings, each of which is roughly the size of a deck of cards. You should eat a variety, emphasizing fatty fish like salmon, herring, and sardines. These foods provide healthy omega-3 fatty acids.
“That said, eating seafood daily raises a concern about health risks associated with the trace amounts of mercury found in seafood. Some varieties contain elevated levels that can be harmful if eaten frequently. In general, mercury toxicity is not a concern for people who eat modest amounts of fish (1 to 2 servings per week).
“To reduce your mercury intake if you eat fish frequently (more than five times per week), consume a variety of seafoods and avoiding those species highest in mercury. Larger and longer-living fish tend to have the highest levels of mercury, specifically king mackerel, marlin, orange roughy, shark, swordfish, tilefish, and albacore tuna (including solid or chunk white canned tuna).
“The best fish choices are those that are rich in omega-3s yet low in mercury. These include salmon (farmed or wild), herring, anchovies, sardines, trout, and Atlantic and Pacific mackerel.”