Bob DeMarco Alzheimer's Reading Room

Thursday, May 19, 2011

Mediterranean Diet and Exercise Reduces the Risk of Alzheimer's


We now know that genetics and genetic changes play a role in Alzheimer's disease. As time goes on these mysteries are slowly being unraveled. We also know that non-genetic changes, including lifestyle and behavior, may also be affecting our brain health and our risk of developing brain diseases, like Alzheimer’s, maybe in combination with our genetic predisposition.

Alzheimer's Reading Room

***May is Mediterranean Diet Month***

Mediterranean Diet and Exercise Reduces the Risk of  Alzheimer's
Jay Smith wrote previously about his own program of healthy diet and supplements, mental and physical exercise, and socialization and creative self-expression -- This Man Decided to Fight Alzheimer's -- Jay Smith.

Jay's article reminded me of the 18 studies that were previously published on the Alzheimer's Reading Room on these issues. This includes the sudy below that first appeared on the ARR in 2009.

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Researchers studied the combination of exercise and the Mediterranean diet to determine if they helped reduce the risk of Alzheimer's disease.

Please understand there is no magic bullet. This studies findings do not say if you exercise and eat a Mediterranean diet you won't get Alzheimer's disease. However, there are a long list of incidental studies that indicate a healthy diet and exercise might play a role in delaying the onset of Alzheimer's; and/or, slow the progression of Alzheimer's disease.

Many of the world's top scientist believe that lifestyle choices can make a difference.

The research study found that
  • those subjects who were very physically active had a 33 percent risk reduction of Alzheimer’s,
  • those who adhered more strongly to a Mediterranean-type diet had a 40 percent risk reduction.
  • found that there was a gradual decreasing risk for Alzheimer’s in study participants who were reporting that they were both exercising a lot, and following a diet closer to the Mediterranean-type: those subjects had a 60 percent reduction in their risk for developing Alzheimer’s disease.

Exercise and Mediterranean-type Diet Combined Appear to be Associated with Lower Risk for Alzheimer’s Disease

Findings of Observational Study Warrant Further Research in Controlled Clinical Trial to Clarify the Role of These and Other Possible Factors Contributing to AD Risk

Both being more physically active and adhering to a Mediterranean-type diet appears to be associated with reduced Alzheimer’s risk, according to a report in the August 12, 2009 issue of the Journal of the American Medical Association (JAMA).

While previous studies have only investigated the association between either physical activity or diet and Alzheimer’s disease risk separately, this new research explored their combined association.


“Often times people who exercise also follow a healthy diet and vice versa. We wanted to tease out which of these two behaviors may be associated with lower risk for AD, or if the combination of the two is associated with decreased risk even further,” said Nikos Scarmeas, M.D., lead author of the study and associate professor of clinical neurology in the Department of Neurology, in the Sergievsky Center and in the Taub Institute for Research on Alzheimer’s Disease and the Aging Brain at Columbia University Medical Center.

This population-based study in a multi-ethnic community living in Northern Manhattan, observed 1880 elderly subjects, with an average age of 77. The participants were interviewed about their level of physical activity and dietary habits, and their responses were then summarized into two single scores. The study subjects were then followed to observe which subjects went on to develop Alzheimer’s over the course of approximately five and a half years.

To learn about their physical exercise routine, participants were queried about their activity during a two week period prior to the interview. The subjects were asked to quantify how many times they engaged in physical activity and for how long. Participants were queried regarding three categories of activities: vigorous activity (i.e., jogging etc), moderate activity (i.e., hiking, bicycling, etc), and light activity (i.e., golfing, gardening, etc).

For the dietary portion of the study, subjects were asked regarding their food consumption over the course of the previous year. Their responses were then grouped into nine food categories, the sum of which represented the Mediterranean-type diet score. A Mediterranean-type diet is typically characterized by high intake of fish, vegetables, legumes, fruits, cereals and monounsaturated fatty acids; relatively low intake of dairy products, meats and saturated fats; and moderate alcohol consumption.

The study found that those subjects who were very physically active had a 33 percent risk reduction of Alzheimer’s; those who adhered more strongly to a Mediterranean-type diet had a 40 percent risk reduction. In addition, Dr. Scarmeas and his colleagues found that there was a gradual decreasing risk for Alzheimer’s in study participants who were reporting that they were both exercising a lot and following a diet closer to the Mediterranean-type: those subjects had a 60 percent reduction in their risk for developing Alzheimer’s disease.

“So it seemed that the more that they were doing in terms of both diet and exercise, the lower was their risk for the disease,” said Dr. Scarmeas.

Dr. Scarmeas further noted that even low degrees of physical activity reported by these elderly study subjects seemed to be associated with having a protective effect against Alzheimer’s.

“This study is important because it shows that people may be able to alter their risk of developing Alzheimer’s by modifying their lifestyles through diet and exercise,” said Dr. Scarmeas.

Dr. Scarmeas cautions, however, that this was an observational, epidemiological study – based on interviews with study subjects on their physical activity routines and dietary habits. Therefore, the associations were based on what subjects reported and no randomized interventions were done. Only a clinical trial type of design would offer additional information to help clarify the role of these behaviors and reveal other potential contributing factors.

“We know that some part of Alzheimer’s is related to genetic changes and as time goes on we discover more and more of these changes. But it is also possible that non-genetic changes, including lifestyle and behavior, may also be affecting our brain health and our risk of developing brain diseases, like Alzheimer’s, maybe in combination with our genetic predisposition,” said Dr. Scarmeas. “We need to understand and learn more about the exact biological mechanisms that may connect physical activity and diet with the biological changes of Alzheimer’s disease.”

“Since the benefits of following a healthy diet and remaining active have already been suggested as beneficial in other disease prevention and since based on the present and other similar studies we have some preliminary hints that this may also be helpful for brain health, it seems advisable that we emphasize not only to patients, but to healthy individuals, too, the importance of these lifestyle behaviors in affecting our overall health,” said Dr. Scarmeas.

Authors of the JAMA study include: Nikolaos Scarmeas, M.D.; Jose A. Luchsinger, M.D.; Nicole Schupf, Ph.D.; Adam M. Brickman, Ph.D.; Stephanie Cosentino, Ph.D.; Ming X. Tang, Ph.D.; and Yaakov Stern, Ph.D.

This study was supported by the National Institute on Aging.

Also see What is a Mediterranean Style Diet?

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Bob DeMarco
Bob DeMarco is the Founder of the Alzheimer's Reading Room and an Alzheimer's caregiver. The ARR knowledge base contains more than 3,811 articles with more than 306,100 links on the Internet. Bob lives in Delray Beach, FL.

Original content Bob DeMarco, the Alzheimer's Reading Room