Mercury in fish: Experts recommend smaller species to reduce exposure

To reduce mercury exposure, consumers should prioritize smaller fish species over large predatory ones. According to nutritionist and food technologist Beatriz Robles, mercury undergoes bioaccumulation in aquatic environments, converting into methylmercury. As it moves up the food chain, concentrations increase in larger, long-lived predatory fish.

The Spanish Agency for Food Safety and Nutrition (AESAN) identifies swordfish, red tuna, certain shark species, and pike as high-risk options due to these elevated levels. AESAN recommends that pregnant women, breastfeeding mothers, and young children avoid these high-risk species entirely.

For the general population, experts suggest consuming 3-4 servings of fish per week, alternating species and favoring smaller fish. Notably, fat content is not an indicator of mercury levels; many fatty fish, such as sardines, anchovies, mackerel, herring, and salmon, are considered low-risk and provide essential omega-3 fatty acids like EPA and DHA.