The benefits of omega-3 fatty acids seem to outweigh possible harm from mercury.
In 2004, in an effort to reduce fetal neurotoxicity from mercury exposure, the U.S. government advised pregnant women to limit seafood intake to 340 g per week or less. However, seafood is an important source of omega-3 fatty acids that are essential to fetal neurodevelopment.
U.K. researchers reanalyzed data from a cohort study of 8946 pregnant women that began in 1991. (British and U.S. seafood mercury levels are similar.) Periodically during and after their pregnancies, the women provided information about their diet, education, and social circumstances and their children’s development. Each child underwent a standard intelligence test at age 8.
The data were adjusted for 28 potentially confounding variables, including birth outcomes, soci…