October 22, 2007
A Mediterranean diet rich in fruits, vegetables, and whole grains may help people with Alzheimer's disease live longer than those who eat a more traditional Western diet. The findings bolster a growing body of evidence that the traditional diet from Italy, Greece, and other countries that lie along the Mediterranean Sea high in fiber and heart-healthy fats like olive oil, along with moderate amounts of red wine and little red meat are good for the body and brain and may promote longevity and cognitive health. The findings appeared in Neurology, the medical journal of the American Academy of Neurology.
Researchers from Columbia University Medical Center in New York regularly examined 192 people with Alzheimer's disease over an average of four and a half years. During that time, 85 of the people died. They found that those who most closely followed a Mediterranean diet were 76 percent less likely to die during the study period than those who ate few of the Mediterranean-type foods. The benefits persisted, regardless of race or ethnicity.
"The more closely people followed the Mediterranean diet, the more they reduced their mortality," said study leader Nikos Scarmeas, MD, MSc. "For example, Alzheimer's patients who adhered to the diet to a moderate degree lived an average 1.3 years longer than those people who least adhered to the diet. And those Alzheimer's patients who followed the diet very religiously lived an average four years longer."
Previous research by Scarmeas and his colleagues demonstrated that healthy people who eat a Mediterranean diet lower their risk of developing Alzheimer's disease. Studies have also shown that healthy people who follow a Mediterranean diet live longer than those who eat a more traditional Western diet high in saturated fat and meats and lower in fruits and vegetables.
"New benefits of this diet keep coming out," said Scarmeas. "We need to do more research to determine whether eating a Mediterranean diet also helps Alzheimer's patients have slower rates of cognitive decline, maintain their daily living skills, and have a better quality of life."
Earlier studies have shown that a Mediterranean diet may cut the risk of heart disease, cancer, diabetes, and possibly other maladies as well.
Doctors are not sure why a Mediterranean diet may be good for the brain. One possibility is that such a diet reduces a risk for blood vessel disease, which may contribute to the risk for Alzheimer's disease. A Mediterranean diet helps cut down on inflammatory substances in the body, too, and inflammation has increasingly been tied to heart disease and possibly Alzheimer's as well. Fruits, vegetables, and red wine are also high in cell-protecting antioxidants.
The Mediterranean diet has long been advocated as a heart-healthy diet to ward off heart attacks and strokes. The main elements of the Mediterranean diet include:
-An abundance of plant foods, such as fruits, vegetables, cereals, nuts, and beans;
-Using "good" fats, such as olive or canola oil, rather than butter or lard, and limiting dairy products like high-fat cheese and milk;
-Eating moderate amounts of fish and poultry, rather than red meat; and
-Drinking a glass or two of red wine a day.
Many other factors besides diet, including the genes you inherit and advancing age, play an important role in who ultimately develops Alzheimer's. Still, the findings add to a growing body of evidence that a heart-healthy lifestyle, with plenty of exercise, a sound diet, not smoking, and keeping weight down, may help keep the brain young.
"In the case of Alzheimer's disease, not only do dietary changes appear important, but evidence now exists that exercise and mental stimulation may also reduce risks and consequences of the disease, such as modifying the course of cognitive decline and delaying mortality," write Dr. James El Galvin of Washington University School of Medicine in an editorial accompanying the study.
"It is interesting that considering all the medical and pharmaceutical advances made in the last century," he adds, "perhaps the most important things we can still tell our patients, regardless of why they come to the office, is to stay mentally active and physically fit and to eat a healthy a balanced diet."
The Fisher Center for Alzheimer's Research Foundation continues to fund vital research into the underlying causes of Alzheimer's and the search for a cure. For more on ways to maintain your brain, visit www.ALZinfo.org.
Nikolaos Scarmeas, MD, Jose A . Luchsinger, MD, Richard Mayeux, MD, Yaakov Stern, PhD: "Mediterranean Diet and Alzheimer Disease Mortality." Neurology, Volume 69, September 11, 2007, pages 1084-1093.
James E. Galvin, MD: "Pass the Grain, Spare the Brain"; editorial; Neurology, Volume 69, September 11, 2007, pages 1072-1073.