Eating Baked or Broiled Fish Helps Improve Brain Health

Weekly consumption of baked or broiled fish is known to boost memory and cognition, a new study reveals.

The researchers at the University of Pittsburgh School of Medicine found that eating baked or broiled fish on a weekly basis helps in improving brain health, irrespective of the amount of omega-3 fatty acid it contains. The study supports the previous theories that lifestyle factors contribute to brain health later in life.

Senior investigator James T Becker noted that by 2040, it is estimated that 80 million people will be diagnosed with dementia - which would not only be a burden on families, but will also increase health care costs. 

The research conducted earlier linked changes in lifestyle to drop in Alzheimer's disease and other conditions of cognitive impairment in the elderly. Changes in lifestyle include lower rate of physical inactivity, smoking and obesity. The anti-oxidant effect of omega-3 fatty acids - present in high amounts in fish, nuts, seeds and certain oils - is linked to improved health, especially 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," Dr. Becker said. "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."

The study led by Cyrus Rajii evaluated data of 260 people - who provided information on their diets. They had undergone MRI scans and were cognitively normal at two time points while taking part in the Cardiovascular Health Study, which began in 1989, to identify the risk factors for heart disease in people above 65 years of age.

"The subset of CHS participants answered questionnaires about their eating habits, such as how much fish did they eat and how was it prepared," Dr. Raji said. "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."

The researchers noticed that the participants who consumed baked or broiled fish at least once a week had greater grey matter volume in the brain regions responsible for memory (4.3 percent) and cognition (14 percent). These people were more likely to have college education as compared to those who didn't eat fish regularly. However, there was a relationship between the brain differences and blood levels of omega-3s.

"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 is responsible for better brain health, and this reserve might prevent or delay cognitive problems that can develop later in life."

The finding was documented in the American Journal of Preventive Medicine.