Turns Out, Fish as Brain Food is no Myth
Chicago Sun Times
October 11, 2005

BY JIM RITTER Health Reporter

Eating fish just once a week significantly slows down cognitive decline in older adults, according to a new study.

The decline in memory, mental speed and other cognitive abilities was slowed by 10 percent among people who ate one fish meal per week and 13 percent among those who ate two or more meals a week.

This is equivalent of being three to four years younger in mental age, report researchers from Rush University Medical Center.

Eating fish "may help preserve our thinking ability as we get older," said lead researcher Martha Clare Morris. The study is published in the Archives of Neurology.

Researchers surveyed 3,718 people over age 65 who participated in the Chicago Health and Aging Project. Participants were given cognitive tests and asked detailed questions about their eating habits. They were followed for six years.

May also help younger people

Earlier studies found that eating fish reduces the risk of Alzheimer's disease. The new study found that fish also is good for people who experience normal cognitive decline as they age, such as forgetting names or having difficulty recalling words.

It's a good bet that eating fish also could boost cognitive abilities of people younger than 65, although this hasn't been proven, Morris said.

Obesity linked to Alzheimer's?

It's unclear why fish is good brain food. It may be due in part to omega-3 fatty acids in fish. Another possibility is that when people eat fish, they consume fewer portions of other foods that might be bad for the brain, Morris said.

But one downside of fish is that it contains trace amounts of toxic mercury. The federal government advises young children and women who are nursing, pregnant or might become pregnant to avoid fish high in mercury, including swordfish, shark, king mackerel and tilefish.

In another article in Archives of Neurology, Swedish researchers reported that obesity in middle age roughly doubles the risk of Alzheimer's disease later in life. Researchers noted that obesity has been linked to vascular disease, which in turn has been linked to dementia and Alzheimer's disease.

The study also found that high blood pressure and high total cholesterol each roughly doubled the Alzheimer's risk. People who were obese and had high cholesterol and high blood pressure had six times the risk of Alzheimer's.

But the link between obesity and Alzheimer's is controversial. A Rush study published last month reached the opposite conclusion: Researchers found that losing weight was associated with an increased risk of Alzheimer's.

Source:
http://www.suntimes.com/output/health/cst-nws-fish11.html
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