Can Fish Protect You From Pollution?

Eating more than two servings of shellfish or baked or broiled fish per week could help protect the brains of older women from the detrimental effects of air pollution, a study has found. Conducted by scientists from Columbia University in New York, the research involved over a thousand women with an average age of 70 years and determined that the omega-3 fatty acids contained within the seafood could reduce the impact of pollutants on their brain’s functionality.

This particular study focused exclusively on older women, meaning its results cannot be extrapolated across wider populations. But as an ingredient which can be easily assimilated into most diets without a problem, the study does provide some evidence that fish could provide a straightforward method for those exposed to poor air quality on a regular basis to safeguard their mental capacity.

Brain food

The research began by asking 1,315 women with an average age of 70 to fill out a questionnaire regarding their dietary habits. These answers were then cross-referenced against data collected by sophisticated air quality monitoring technology to determine the pollution levels to which they were exposed. They were also subjected to magnetic resonance imaging (MRI) scans to quantify volumes of white matter and hippocampus in their brains.

The results showed that those participants with higher levels of omega-3 in their bloodstream had greater volumes of both white matter and hippocampus in their MRI readings. What’s more, they found that the white matter was less affected by air pollution in those who included fish and seafood in their diet. Every quartile increase in air pollution was matched by an average drop-off of 11.52cm³ in white matter in those who had reduced levels of omega-3, compared to a reduction of just 0.12cm³ in those with plentiful levels of the substance.

Food for thought

The limitations of the study (with specific regard to the narrow demographics of its participants and the relatively short length of its duration) mean that it is difficult for the authors to make bold predictions about the effects of eating fish on the brain, but they were optimistic with the results. “Our findings suggest that higher levels of omega-3 fatty acids in the blood from fish consumption may preserve brain volume as women age and possibly protect against the potential toxic effects of air pollution," explained Ka He, lead author on the study.

“It's important to note that our study only found an association between brain volume and eating fish. It does not prove that eating fish preserves brain volume. And since separate studies have found some species of fish may contain environmental toxins, it's important to talk to a doctor about what types of fish to eat before adding more fish to your diet.” He’s work is symptomatic of a growing public awareness surrounding the pitfalls of air pollution, as was also evidenced the strong turnout at the Air Quality Emissions convention in late 2018.