Nutrition Bytes

While environmental pollution has demonstrated the neurotoxic and teratogenic effects of methylmercury, the risk of damaging the developing brain by consuming fish that naturally contain a much smaller mercury concentration is yet to be determined. The current belief and precaution is that for pregnant women and young children, this risk outweighs the many benefits of fish consumption. Landmark studies conducted in the Faroe Islands and the Republic of Seychelles, respectively, have yielded conflicting outcomes in cognitive function in children who have been exposed both pre- and postnatally to methylmercury concentrations more than 10 times that seen in the United States. Faroese children demonstrated some cognitive deficits in language, attention, and memory, while the Seychellois did not manifest any. The confusion may likely be explained by dietary differences, particularly in seafood consumption, as well as differences in genetic endowment. Nevertheless, more cohort, animal, and other investigative studies must be conducted in order to understand not only the mechanism of methylmercury-mediated toxicity in the developing brain, but also the exact risks of maternal fish consumption, for the sake of effective health policy and the mental health of our posterity.