The Mediterranean diet, a weight-loss method based on the idea that the traditional cuisine of Mediterranean countries was especially healthy, became popular a few years ago. Now, a new study, funded by the Spanish government and published in JAMA Internal Medicine, has shown that this diet can counteract the effects of aging in the brain.
“This was the first clinical, randomized study using a dietary pattern for good health,” said Emilio Ros, a researcher associated with the University of Barcelona.While previous observational research shows that the diet had cognition related benefits, observational studies have limitations. “This clinical trial removes the bias and provides first-level evidence,” said Dr. Ros.
The Mediterranean diet comprises fruits, nuts, olive oil, garlic, vegetables, and unrefined grains, among other things. It also encourages the consumption of fish and red wine instead of meat and spirits.
The latest study tested 447 people aged 55-80, divided into groups. Two groups followed the Mediterranean diet and added either 30 grams of mixed nuts or five tablespoons of extra virgin olive oil a day. The third group, acting as a control, was advised to follow a low-fat diet. The subjects were tracked for four years.
The results showed that the Mediterranean diet + nuts group showed stronger memory, while frontal (attention and executive function) and global cognition increased in the Mediterranean diet + olive oil group, compared to the control subjects.
Cognitive function may have been enhanced by the diet’s richness in antioxidants and anti-inflammatory compounds found in nuts and olive oil. Both foods are rich in phenolic compounds that can counteract oxidative processes in the brain, leading to neurodegeneration, the study said.
Jane Cerhan, a clinical neuropsychologist at the Mayo Clinic in Rochester, Minn., qualified the study results: “The changes observed in cognition were very small and didn’t actually show that those diets improved cognition, they just showed less decline.”
Dr. Ros previously tested the Mediterranean diet for cardiovascular related benefits, finding that the diet reduced the incidence of major cardiovascular events among high-risk people.