Nuts, Vegetables, Fish Cut Alzheimer's Risk
Study Shows a Heart-Healthy Diet May Also Be Good for the Brain
Oct. 15, 2009 (Baltimore) -- A diet rich in cruciferous and green leafy
vegetables, nuts, fish, and tomatoes and low in red meat and high-fat dairy
products may protect against Alzheimer's disease, a study suggests.
Researcher Nikolaos Scarmeas, MD, associate professor of neurology at
Columbia University in New York, tells WebMD that recommendations can't be made
on this study alone. "But in general, these foods are part of what we consider
a healthy diet for other reasons, such as protection against heart disease. And
they could help [your brain]."
The study was presented at the annual meeting of the American Neurological
The research involved 1,691 people aged 65 and older with no signs of
dementia when they entered the study. All filled out detailed questionnaires
that asked about what foods they ate over the past year.
The researchers then studied various foods in the lab to determine which
were rich in nutrients such as omega-3 fatty acids and vitamin E that have been
linked to a lower risk of Alzheimer's disease and which were low in nutrients
such as saturated fatty acids that have been linked to a greater risk.
Based on the amounts of each nutrient in each food, "we discovered an
Alzheimer's-disease-protective dietary pattern that was characterized by a high
consumption of nuts, fish, salad dressing, poultry, tomatoes, cruciferous,
dark, and green leafy vegetables and fruits, and low in high-fat dairy, red
meat, organ meat, and butter," Scarmeas says. "Foods are not consumed in
isolation, so studying the dietary pattern may offer substantial
The 1,691 study participants were then divided into three groups according
to how well they adhered to such a diet over the past year. Over the next four
years, 211 of them were diagnosed with Alzheimer's disease. Results
showed that those in the top third were 38% less likely to develop Alzheimer's
four years later than those in the lowest third.
The analysis was adjusted for a variety of factors that could potentially
explain the association, including age, smoking status, physical activity, body
mass index, and caloric intake.
The fact that the researchers followed healthy people over time and that the
analysis was adjusted to take into account factors such as physical activity
that may also lower the risk of Alzheimer's disease gives it strength, says
Craig Blackstone, MD, PhD, of the National Institute of Neurological Disorders
"This is certainly a healthy diet to follow," he says.