September 30, 2024 โ Ahi steak. Akami sashimi. Albacore on sourdough. Whether you smoked yellowfin on the grill or spread skipjack on a sandwich, chances are youโve had tuna recently.
On average, Americans eat around two pounds of the fish per year, more than any other seafood except for shrimp and salmon. And for good reason: Tuna is tasty and versatile, and the canned variety costs as little as a dollar.
But is it good for you? Should you be worried about its mercury content? And what about the health of our oceans? Hereโs what to know before you pop open that next can for lunch.
Is tuna healthy?
Tuna is about as nutritious as a food can be.
Itโs packed with protein, minerals and vitamins, said Chris Vogliano, a dietitian and research director at the educational nonprofit Food and Planet. It has more selenium than just about any other meat. Itโs also low in fat, Dr. Vogliano noted โ but that means it has fewer omega-3 fatty acids than some other seafood.
Thereโs not a huge nutritional difference between canned tuna, sushi and a tuna steak, he added. Cooking the fish might lower its vitamin D, and the canning process might leach out a few nutrients, he said, but its nutritional value is largely the same.
Tunaโs one big health drawback, experts say, is the risk posed by mercury, a neurotoxin. This heavy metal enters the ocean mostly from human activities like burning fossil fuels. Itโs absorbed by small organisms and works its way up the food chain and accumulates in bigger, longer-lived species โ like sharks, swordfish and, yes, tuna.
In high enough concentrations, mercury can cause serious health problems. Cases of mercury poisoning are rare in the United States, but experts worry about the long-term effects of mercury on the brain โ and elevated levels are often more common among urban and coastal populations that eat more seafood.
So what does this mean for tuna eaters? The answer is nuanced because the amount of mercury depends on the species โ and there are 15 types of tuna, all of which could end up on a dinner plate. The smallest (and often cheapest), like skipjack, have very little mercury. Albacore and yellowfin can have three times as much; bigeye and bluefin can have far more, Dr. Vogliano said.