Omega-3 fatty acids may protect the brain from mercury damage

A new study reports that the benefits of consuming fish rich in omega-3 fatty acids on prenatal development may offset the risks associated with mercury exposure.

The observational study measured the blood concentrations of polyunsaturated fatty acids (PUFA) and the mercury levels in hair samples of 1265 pregnant mothers from the Seychelles (1). At 20 months after birth, their children’s communication skills, behavior, and motor skills were tested. The study results showed that the children of mothers with higher levels of omega-3 fatty acids during pregnancy performed better in the neural development tests. Children of mothers with relatively higher levels of omega-6 fatty acids did poorer on tests measuring motor skills. The mercury exposure of the women did not correlate with lower test scores.

The scientists concluded that it is becoming increasingly clear that the benefits of consuming fatty fish, which is rich in omega-3 fatty acids, seems to counteract any potentially adverse effects of mercury (through oxidation and inflammation) on brain development. Omega-3 fatty acids are known to have anti-inflammatory properties, compared to omega-6 fatty acids from meat and cooking oils, which can promote inflammation. The Seychelles, a cluster of islands in the Indian Ocean, has proven to be the ideal location to examine the potential health impact of persistent low-level mercury exposure. The nation’s residents consume fish at a rate 10 times greater than the populations of the U.S. and Europe.

1. Strain J. J. et al. Prenatal exposure to methyl mercury from fish consumption and polyunsaturated fatty acids: associations with child development at 20 mo of age in an observational study in the Republic of Seychelles. Am J Clin Nutr. Published online January 2015.