Mercury is a natural element found in very small quantities in the air, water, soil, and all living things. During the past decade, concern over mercury levels in seafood has been the subject of much research and discussion, causing unwarranted alarm about all seafood and general confusion about what is safe to eat.
Researchers have found that, for most people, risk from mercury by eating fish and shellfish is not a health concern, even though all seafood has trace amounts of mercury. The mercury levels in seafood vary widely and most species have very low amounts, usually less than one-tenth of the U.S. established guideline for the allowable level of mercury in fish and seafood products.
Follow these general guidelines to minimize risks that could be associated with mercury in seafood:
- Pregnant and Nursing Moms. The FDA recommends that pregnant and nursing moms eat at least 8 and up to 12 ounces of a variety of seafood per week, from choices that are lower in mercury. Pregnant and nursing moms should avoid the four fish that are highest in mercury: swordfish, shark, tilefish from the Gulf of Mexico, and king mackerel. Another commonly eaten fish, albacore (“white”) tuna, might have more mercury than canned light tuna. When choosing your two meals of fish and shellfish, you may eat up to 6 ounces (one average meal) of albacore tuna per week. The FDA also recommends checking local advisories for varieties of fish you catch yourself in your local lakes, rivers, and coastal areas. If no advice is available, eat up to 6 ounces (one average meal) per week of fish you catch from local waters, but don't consume any other fish during that week. Advisories are available from local and state health departments, as well as the U.S. Environmental Protection Agency.
- Young Children. Because their brains are still developing, the FDA recommends that young children follow the same guidelines as pregnant and nursing moms—at least 8 and up to 12 ounces each week of seafood low in mercury. For children ages 6 months to 8 years, the USDA Food Patterns provide examples of the types and amounts of seafood to consume for health (see response #9 under Questions and Answers).
- Everyone Else. Eat 8 or more ounces per week of a variety of seafood—with no recommendations to avoid any seafood. Dark and oily fish provide the most omega-3s, but eating a variety of seafood will provide balanced nutritional benefits and please your palate.