Fish consumption could boost seniors' brain health: study

This baked Florida snapper dish could be more than just tasty: It could promote better brain health, according to new research that shifts the focus away from omega-3s. (ifong/shutterstock.com)

A study conducted at the University of Pittsburgh Schools of the Health Sciences suggests shifting focus from omega-3s to fish, pure and simple, baked or broiled, for better brain health.

"Our study shows that people who ate a diet that included baked or broiled, but not fried, fish have larger brain volumes in regions associated with memory and cognition," says senior investigator James T. Becker, Ph.D., professor of psychiatry, Pitt School of Medicine.

While studies abound hailing the multitude of health benefits that omega-3 fatty acids offer and associations with brain health account for a large portion of them, Dr. Becker and his team were underwhelmed by the influence of omega-3s in their study.

"We did not find a relationship between omega-3 levels and these brain changes, which surprised us a little," he says. "It led us to conclude that we were tapping into a more general set of lifestyle factors that were affecting brain health of which diet is just one part."

Using high-resolution MRI scans of the brain, lead investigator Cyrus Raji, M.D., Ph.D., who now is in radiology residency training at UCLA, and the research team analyzed data from 260 people who were concurrently participating in the Cardiovascular Health Study (CHS).

The participants, all of whom were over the age of 65, were assessed to be in good cognitive health at two time points during the 10-year study, which began in 1989, and self-reported their dietary intake.

"The subset of CHS participants answered questionnaires about their eating habits, such as how much fish did they eat and how was it prepared," says Dr. Raji. "Baked or broiled fish contains higher levels of omega-3s than fried fish because the fatty acids are destroyed in the high heat of frying, so we took that into consideration when we examined their brain scans."

Researchers conclude that participants who ate baked of broiled fish at least once per week had a grey matter volume that was, on average, 4.3 per cent greater than those who didn't.

Their cognition was superior by 14 per cent and they were more likely to have a college education than non-fish eaters.

Data regarding blood levels of omega-3s, however, revealed no association between the latter and the differences in cognition and grey matter.

"This suggests that lifestyle factors, in this case eating fish, rather than biological factors contribute to structural changes in the brain," Dr. Becker noted. "A confluence of lifestyle factors likely are responsible for better brain health, and this reserve might prevent or delay cognitive problems that can develop later in life."

The study was published in the American Journal of Preventive Medicine.