Is it safe to eat canned tuna during pregnancy in olive oil or water?

What's actually in it

Canned tuna comes from several species. Skipjack ("light" tuna) is the smallest and lowest-mercury. Albacore ("white" tuna) is larger and runs about three times higher. Yellowfin and bigeye (the tuna in premium cans and fresh steaks) are higher still. Pregnancy mercury limits assume the FDA's per-serving tables, which a weekly habit can push past.

The can itself adds its own issues: BPA or BPA-substitute liners, and oil vs. water packing changes how metals and chemicals behave.

What the research says

A 2026 study in NPJ Sci Food measured total mercury exposure through canned tuna in oil sold in Quito, Ecuador. Oil-packed tuna had high mercury levels on average, and regular consumers (weekly or more) exceeded tolerable intake. Water-packed versions generally test lower than oil-packed, though the difference varies by brand and source.

FDA guidance for pregnant women: up to 2 servings a week of skipjack light tuna, no more than 1 serving a week of albacore, and avoid bigeye, swordfish, king mackerel, and shark. Water-packed light tuna from Wild Planet or Safe Catch (both publish per-can mercury testing) is the cleaner pick. Varying protein sources (salmon, sardines, chicken, beans) rotates you off the tuna week by week.