A “Mediterranean” diet was associated with a lower risk of Alzheimer’s disease among Americans participating in a new study, researchers reported.

A Mediterranean diet is one with plenty of fruits, vegetables, legumes, cereals, some fish and alcohol, and little dairy and meat. Previous studies have also linked the diet with longer lives, and other health benefits.

In the new research, Nikolaos Scarmeas of Columbia University Medical Center in New York City and colleagues studied 2,258 older New Yorkers for a period of four years.

During that time, 262 were diagnosed with Alzheimer’s—a devastating, progressive degeneration of the brain, estimated to affect 4 million Americans.

But “higher adherence to the Mediterranean diet was associated with significantly lower risk of developing Alzheimer’s disease,” the researchers reported. The findings appear in the April issue of the research journal Annals of Neurology.

Alzheimer’s typically starts in the 40s or 50s with memory difficulties, followed by impaired thought and speech and finally total helplessness.

Researchers scored each participant on a scale from 0 to 9 based on how well they followed a Mediterranean Diet. Each one-point increase, indicating stricter adherence to the diet, was associated with a 9- to 10-percent lower Alzheimer’s risk, they reported.

The scientists said the link remained significant after accounting for age, gender, race, education, caloric intake, body fat, smoking and other illnesses.

A possible weakness of the study was inaccurate measurement of subjects’ diets, the researchers said. But they argued that they had used a previously tested assessment method, and that errors may have actually led to underestimation of the link between the diet and disease. Another possible shortcoming of the study was misdiagnosis of the disease, they noted. But they added that experienced practitioners had made the diagnoses.

Other health benefits of the Mediterranean diet have been shown to apply to a wide range of populations, the researchers said.

ABOUT THE AUTHOR

Science writer Jack Lucentini is founder and editor of the World Science science news webzine. He has worked as a staff writer at three daily newspapers, and as a freelance science writer for a range of publications including The Washington Post, Discover magazine and The Scientist magazine. He earned his bachelor's degree at Oberlin College in Oberlin, Ohio in 1993.