Tuna and mercury

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Your question:

I heard that albacore tuna is high in mercury and should be avoided. Isn’t this fish good for us?

The expert answers:

Albacore (white) tuna is low in saturated fat and a good source of omega-3 fat that seems to help protect against cancer and heart disease.

Albacore tuna is not as high in mercury as shark and swordfish, but tests rank it as “medium” in content, along with haddock, halibut, grouper and several other fish. Too much mercury in food does pose health risks, especially to the nervous system of babies. Therefore, to control exposure to mercury, Food and Drug Administration (FDA) officials recommend that women who are pregnant, breastfeeding, or who might become pregnant limit albacore tuna to one serving a week. These women should restrict their total consumption of all fish and shellfish each week to 12 ounces. Other adults may prefer to do the same because a few studies suggest a link between excess mercury in the diet and heart risks.

But for everyone except these women, current official recommendations consider slightly more white tuna and more total seafood each week safe. It should be noted that canned light tuna is lower in mercury than regular tuna, but it is an unreliable source of omega-3 fat. In sum, although foods clearly labeled good or bad may comfort us all, albacore tuna is an example of how a food can be healthful, even though it’s not advisable to eat it daily.