fat & dementia

Doug Skrecky (oberon@vcn.bc.ca)
Mon, 2 Aug 1999 01:01:36 -0700 (PDT)

>From LOWCARB Digest - 28 Jul 1999 to 29 Jul 1999 (#1999-175)
Date: Wed, 28 Jul 1999 18:54:16 -0400 From: Dean Esmay <esmay@SYNDICOMM.COM> Subject: Fat & dementia

Low-Fat Diet, Dementia Linked

Low-Fat Diet, Dementia Linked
Associated Press Writer

HONOLULU (AP) _ Researchers studying dementia say they have uncovered a possible health benefit to the relatively fatty Western diet, but they caution against changing eating habits based on the finding.

A study funded by the National Institute on Aging and the Department of Veterans Affairs found that a diet high in animal fat and protein may protect against the onset of dementia in people who have suffered a stroke. The study was published in the July 22 issue of the journal Neurology.

The findings are the latest from an ongoing study of cardiovascular disease that began in 1965 and initially involved more than 8,000 Japanese-American men living in Hawaii.

Fewer than half the participants of the Honolulu Heart Program are still living. The Honolulu-Asia Aging Study, begun in 1991, is a part of the program that deals with dementia.

Researchers compared the dietary preferences of 68 study participants who had developed dementia as a result of a stroke with the preferences of 106 participants who had had a stroke but were not suffering from dementia, and 3,335 participants who had had neither a stroke nor dementia.

They found that those who preferred a Western diet _ higher in animal fat and protein and lower in complex carbohydrates than a traditional Asian diet _ were roughly 57 percent less likely to develop dementia after a stroke. They also found a lower incidence of stroke-related dementia in people who took vitamin E supplements.

Study participants, born between 1900 and 1919, answered questions about their food preferences when the study began in 1965.

``This shouldn't be interpreted as advice to go and get in line at the Burger King or McDonald's,'' said Dr. G. Webster Ross, co-principal investigator of the aging study and a neurologist with the Honolulu VA Medical Center.

He said the study did not determine exactly what foods and nutrients in the Western diet may be most important in preventing dementia after a stroke. Future research will attempt to do that, he said.

But Ross said studies in animals suggest that higher amounts of animal fat and protein in the diet may contribute to better stability of blood vessel walls in the brain.

Stroke-related, or vascular, dementia is the nation's second-leading cause of dementia after Alzheimer's disease, which afflicts about 4 million people in the United States. An estimated 1 million to 2 million people in the United States suffer from vascular dementia, a deterioration of emotional and cognitive abilities that can affect memory, language, reasoning and personality traits.

Dr. Helen Petrovitch, co-principal investigator of the Honolulu aging study, said the study accounted for previously known factors related to dementia such as age and education.

The highest prevalence of dementia was found in the oldest study participants. The study also found that controlling hypertension, diabetes and other risk factors could help prevent strokes and vascular dementia.

Ross said that by studying the same group of first- and second-generation Japanese-Americans over three decades, researchers have been able to compare environmental and cultural differences between the United States and Japan while keeping genetic factors constant.

Dr. James Mortimer, director of the Institute on Aging at the University of South Florida in Tampa, called the Honolulu findings ``very interesting.''

``As far as I know it's the first time that anyone has looked at the issue this way. People have looked at diet and stroke, but no one has looked at diet and (stroke-related) dementia,'' he said.

Mortimer said the findings may be related to the fact that the relatively high-salt Japanese diet is associated with an increased stroke risk. High salt consumption is related to hypertension, a common factor in strokes.

University of South Florida epidemiology professor Amy Borenstein Graves, who is married to Mortimer, said the study adds an intriguing twist to her own finding that the general Japanese lifestyle is associated with a lower risk of cognitive decline. She said she hasn't studied the impact of diet, specifically.

Borenstein Graves has collaborated with the Honolulu-Asia Aging Study as co-principal investigator of the Ni-Hon-Sea Project, a broader dementia research effort involving Japanese and Japanese-American populations in Seattle, Honolulu and Hiroshima, Japan.

``This is an exciting study because it's one of several new studies showing an association between dementia and Japanese lifestyle,'' Borenstein Graves said.

But she said until more is known, people with low-fat diets should not eat more fat based on the findings because they could increase their risk of heart disease.

Additional note from reposter:

Monosaturated and omega-3 fats have also been linked to a reduced risk of cognitive decline.