Eat more like a Greek, and less like a typical American, and you may be doing your brain a favor, new research suggests.

Older adults who adhere to the heart-healthy Mediterranean diet -- rich in fruits, vegetables, olive oil, legumes, fish, and moderate amounts of wine -- appear to have less mental decline with age, according to one of the latest studies on the health benefits of eating like a Greek.

''Those who adhered most closely to the Mediterranean diet performed as if they were two years younger," says study researcher Christy Tangney, PhD, a researcher at Rush University Medical Center, Chicago, who presented her findings Monday at EB 2010, the annual Experimental Biology meeting.

Exactly why the diet, already known for its heart-healthy effects, may protect brain function isn't known, Tangney tells WebMD, but her research builds on other studies finding the diet preserves thinking and intellectual skills.

''I think there's a strong cardiovascular component," she says. Some of the diet components, such as the phytochemicals from fruits and vegetables, are thought to protect against neuron loss, she says.
Following the Mediterranean Diet

Tangney and her colleagues followed 3,790 men and women enrolled in the ongoing Chicago Health and Aging Project. The average age of the participants was 75, but all were over age 65. The follow-up averaged more than seven years.

The men and women answered a food-frequency questionnaire, spelling out in detail which components of the diet they ate and how often. The highest possible score for adherence to the Mediterranean diet is 55, but as Tangney notes, "No one followed it perfectly."

Tangney then classified their adherence to the diet as low, medium, or high. Low followers scored 12 to 25, medium 26 to 29, and high 30 to 45.

The researchers administered several tests of mental function, such as short- and long-term recall, and compiled those scores as a ''global cognitive score.'' The tests were given every three years.

Those in the top group knocked two years off their test scores, she says. For instance, if they were 65, they scored in the typical range for a 63-year-old.

There was some effect in the medium group, Tangney says, but no effect in the group that adhered the least.

The beauty of the finding, Tangney tells WebMD, is that following the diet perfectly isn't necessary to get a brain-protective effect. "When someone incorporates a diet rich in fruits and vegetables and non-refined grains such as cereals and breads and breaks it up with a little wine, there appears to be at least some protection against cognitive aging," she says.

While Tangney's team didn't inquire about exercise habits, she says physical activity would be ideal to add to the Greek-like diet. "The true Mediterranean diet advocates lots of physical activity," she says.