Should I worry about tuna and mercury?
Fish can be an excellent protein source, and fatty fish can contribute beneficial fats. Mercury risk depends on fish species, amount, and life stage. The FDA/EPA guidance places canned light tuna in a lower-mercury category than albacore or yellowfin, and recommends more caution for people who are pregnant, may become pregnant, breastfeeding, or feeding young children.
For most adults, the practical move is variety: rotate tuna with salmon, sardines, trout, cod, shrimp, tilapia, chicken, lean meats, eggs, dairy, tofu, or legumes. If you eat tuna frequently, choose lower-mercury options more often and follow current public-health guidance for your situation.