SEATTLE, May 1 -- A diet that's high in vegetables, nuts, and fish but low in fatty dairy products may help protect against Alzheimer's disease, researchers said here.

Patients in the highest tertiles of such a diet had a 42% reduced risk of developing Alzheimer's, Yian Gu, Ph.D., of Columbia University, and colleagues said at the American Academy of Neurology Meeting.

"There was a significant relationship for the seven nutrients that are most consistently associated with Alzheimer's disease," Dr. Gu said.

Dr. Gu and her colleagues used the Reduced-Rank Regression model to analyze dietary patterns that might explain the variation of nutrients that is believed to be related to disease risk.

They evaluated the diet via those seven Alzheimer's disease-related nutrients: saturated fats, monounsaturated fats, omega-3 fatty acids, omega-6 fatty acids, vitamin E, vitamin B12, and folate.

The researchers prospectively assessed 2,136 healthy elderly patients in New York who
provided dietary information. Participants were evaluated with the same standardized neurological and neuropsychological measures every one-and-a-half years.

A total of 251 patients developed Alzheimer's disease over the four-year follow-up period.
In a multivariate analysis, the researchers found that a diet high in omega-3, omega-6, folate, and vitamin E, and low in saturated fat and B12, was strongly associated with lower risk of Alzheimer's disease.

Compared with the lowest scores for dietary pattern, the middle and highest tertiles had significantly reduced risks of developing Alzheimer's (HR 0.77, 95% CI 0.56 to 1.05 and HR 0.58, 95% CI 0.40 to 0.84, respectively, P<0.01).

Dr. Gu said the B12 finding was "surprising" since deficiency of the nutrient is associated with dementia. However, a major dietary source of B12 is meat, which is also a large source of saturated fat, she said.

The protective diet was characterized by higher intakes of cruciferous vegetables, green-leafy vegetables, fish, nuts, and tomatoes, and by a lower intake of high-fat dairy products.

Dr. Gu said that further study of Alzheimer's disease-related nutrients can better identify dietary patterns that relate to disease risk. .......report in MedPage Today