Eating fish keeps older people brainy, study says

Fish really is brain food after all, according to a new study, which shows eating fish can slow the mental decline associated with aging.

The results show that eating fish at least once a week slowed the rate of mental or cognitive decline in elderly people by 10 percent to 13 percent per year.

“That rate of reduction is equivalent to being three to four years younger in age,” write researcher Martha Clare Morris, ScD, of Rush University Medical Center, Chicago, and colleagues in the Archives of Neurology.

Their findings were released online today in advance of the scheduled December publication date in the journal.

Researchers attribute the protective effects of fish on the brain to omega-3 fatty acids. Fish, especially oily types like salmon and tuna, are a rich source of omega-3 fatty acids, which are essential for brain development and normal brain functioning.

Eating fish regularly has already been linked to a lower risk of dementia and stroke, and some animal studies show that at least one type of omega-3 fatty acid known as DHA (docosahexaenoic acid) plays an important role in memory performance during aging, reports CBS.

According to Reuters, in another study, Swedish researchers from the Karolinska Institute in Stockholm concluded that obesity, high blood pressure, and high cholesterol levels at midlife each doubled the risk of dementia later in life.

Subjects who suffered from all three of the health problems at midlife multiplied their risk of developing dementia six times compared to people free of the risk factors, she said.

Nearly 1,500 subjects who have been part of a study that began in 1972 were reexamined. The 16 percent who were obese at midlife were at double the risk of dementia compared to the one-quarter of those with normal weight at midlife and the half who had been slightly overweight.

"Midlife obesity, high systolic blood pressure, and high total cholesterol were all significant risk factors for dementia, each of them increasing the risk around two times," study author Miia Kivipelto wrote.

P.T.