Eating fish may protect the brain from pollutants
By Nicholas Bakalar
Eating fish could help protect the brain against the detrimental effects of air pollution, a new study suggests.
Previous studies have shown that exposure to the smallest particles of air pollution, called PM 2.5, is associated with decreases in brain volume, which may increase the risk of memory and thinking problems as we age. This new study, published in Neurology, included 1,315 women ages 65-80 who underwent brain MRI’s to determine brain volume.
The participants filled out questionnaires on their fish consumption and had blood tests to determine their levels of omega-3s, the healthy unsaturated fatty acids found in fish. Using data from the Environmental Protection Agency, the researchers tracked three-year levels of air pollution at the women’s addresses.
The scientists found that women with higher blood levels of omega-3s had significantly greater volumes of white matter in their brains, and the adverse effects of PM 2.5 on brain volume were much smaller in women with high blood levels of omega-3 fatty acids.
Independent of omega-3 blood levels, they found that a small increase in nonfried fish consumption — one 8-ounce serving a week — was also associated with increased white matter volume.
The lead author, Cheng Chen, a postdoctoral researcher at Columbia University, said that while the mechanism remains unknown, “this is one of many studies that demonstrate that a healthy diet can reduce these negative effects of air pollution: neurodegeneration and cognitive decline.”