By Paolo DeAndreis

Common aging process known as brain atrophy has been effectively limited by the adoption of a Mediterranean diet significantly high in polyphenols and low in processed and red meat, known as Green-Med.

A team of researchers from Ben Gurion University in Israel has found significant beneficial effects of Green-Med adoption on a large group of overweight employees at the Dimona Nuclear Research Center. Two hundred twenty-seven participants completed the 18-month trial during which several brain parameters were analyzed.

We could see that the Mediterranean diet and specifically the green-Mediterranean diet, which has much more polyphenols, could actually protect the brain and attenuate age-related brain atrophy.
- Iris Shai, professor of nutrition, Harvard University
The employees were divided into three groups. The first was asked to follow a healthy diet, the second one was instructed to adopt a traditional Mediterranean diet and the third one was asked to follow Green-Med. All of them were also asked to carry out specific physical activities and all were given a free gym membership.

To enhance the high-polyphenol profile of Green-Med, the researchers introduced walnuts and green tea into the diet.

In a note, researchers explained that the polyphenols in walnuts decrease the risk for dementia and reduce brain inflammation. Green tea’s polyphenols are also known for their favorable effects on cognitive function and reduced inflammation in the brain.

While walnuts were also given to the MedDiet group, scientists administered a specific strain of the Wolffia globosa duckweed, Mankai, an aquatic plant rich in protein, to the Green-Med group. Frequently used in Asian cuisine, Mankai is also rich in polyphenols, vitamins and amino acids.

“We guided the participants to prepare a green Mankai shake with additional ingredients, which were also part of the diet regimen (fruits, walnuts or vegetables) each evening,” the researchers wrote. “The green protein shake partially substituted for dinner, replacing beef or poultry protein sources.”

The scientists explained how the participants’ brain structures were evaluated and measured through magnetic-resonance imaging during the trial.

“This 18-month clinical trial longitudinally measured brain structure volumes by magnetic-resonance-imaging using hippocampal-occupancy (HOC) and lateral-ventricle-volume (LVV) expansion scores as neurodegeneration markers,” they wrote.

During the trial, the participants were also asked to perform tests of choice-reaction time and other connected tasks used to estimate and measure specific brain abilities.

Those examinations uncovered how in subjects over 50 years of age HOC decline and LVV expansion were reduced in both MedDiet groups, with the best outcomes among the Green-Med diet participants.

“Improved insulin sensitivity over the trial was the strongest parameter associated with brain atrophy attenuation,” the researchers wrote.

According to the scientists, greater Mankai, green tea and walnut intake and lower red and processed meat consumption were significantly and independently associated with reduced HOC decline.

In their opinion, the complete results show how a Green-Med, high-polyphenol diet, rich in Mankai, green tea and walnuts and low in red and processed meat is potentially neuroprotective for age-related brain atrophy.

“This is the longest and the largest MRI brain trial related to diet or anything,” Iris Shai, co-author of the study, told The Media Line. “We were amazed to see such dramatic changes in 18 months in human beings that we could identify by anatomical structures in the brain.”

“It was actually quite surprising,” she added. “We could see that the Mediterranean diet and specifically the green-Mediterranean diet, which has much more polyphenols, could actually protect the brain and attenuate age-related brain atrophy.”

The good results demonstrated by the group following the traditional Mediterranean diet also confirmed its optimal healthy properties.

Earlier this month, U.S. News & World Report once again named the Mediterranean diet as the best overall diet.

Previous studies have shown its potential effects in preventing cardiovascular and neurodegenerative diseases, diabetes, cancer, degenerative eye diseases and psychological conditions such as depression.

It is also known to foster longevity and its wider adoption falls in line with the 17 goals of the United Nations 2030 Agenda for sustainable development.