Eating fish weekly may prevent brain ageing regardless of omega-3 content: Study

21-Aug-2014 - Last updated on 22-Aug-2014 at 10:35 GMT

Eating baked or broiled fish once a week may prevent age-related grey matter loss, regardless of how much omega-3 fatty acid it contains, according to an American study.

Researchers at the University of Pittsburgh School of Medicine tested 260 cognitively normal individuals over the age of 65 for ten years between 1989 and 1999. Participants were asked to fill out questionnaires about their fish consumption, had blood tests and a magnetic resonance imaging (MRI) of their brains.

The aim of the study was to determine whether dietary fish consumption was related to brain structural integrity among cognitively normal elders.

Brain scans showed that those over 65 who eat fish weekly had larger grey matter volumes in the areas responsible for memory (4.3%) and cognition (14%). They were also more likely to have a university education than those who didn’t eat fish regularly. Grey matter is made up of neuronal cell bodies. It is up a major component of the central nervous system involved in muscle control and sensory perception.

"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," said James Becker, senior investigator and professor of psychiatry at Pitt School of Medicine.

"We did not find a relationship between omega-3 levels and these brain changes, which surprised us a little. 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," Becker added.

Lifestyle over biological factors

It was estimated that more than 80 million people will have dementia by 2040. The findings suggest that lifestyle factors influence brain health and add to the evidence that prevention strategies need to begin decades earlier.

“Our study suggests that lifestyle factors, in this case eating fish, rather than biological factors contribute to structural changes in the brain,” said Becker.

“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,” he added

Source:
American Journal of Preventive Medicine, published online ahead of print 
DOI: 10.1016/j.amepre.2014.05.037
'Regular Fish Consumption and Age-Related Brain Gray Matter Loss'
Authors: J.Becker et al.