A new study found that dietary changes, primarily lowering of blood-sugar levels, can slow the aging of the brain and improve its overall health.

The study, led by Ben-Gurion University of the Negev (BGU), is a follow up to previous research showing that Mediterranean (MED) and Green Mediterranean (Green-MED) diets reduced age-related brain atrophy by 50 percent within 18 months. Both diets include a better-controlled sugar intake.

The current study, published recently in the The American Journal of Clinical Nutrition, sought to understand the exact mechanism that slows brain atrophy, and whether glycemic control and specific dietary aspects play a major role in the process.

As part of the research, participants on MED and Green-MED diets underwent brain MRI scans over a period of 18 months to record the rate of the aging of their brains.

The researchers found that participants who managed to lower their HbA1c levels experienced a more pronounced slowdown of brain aging, including positive changes in specific parts of the brain that are commonly affected by age-related atrophy.

The MRI results also showed that lower HbA1c levels correspond to positive processes in the thalamus, caudate nucleus and cerebellum – areas of the brain crucial for cognitive function, motor skills and sensory processing.

The study’s lead researcher, BGU’s Prof. Iris Shai, said that “maintaining low blood-sugar levels, even within the normal range, shows promise for preserving a younger brain, especially when combined with a healthy diet and regular physical activity.”

Shai is an adjunct professor at Harvard University, and an honorary professor at Leipzig University. 

DIRECT PLUS

The study is part of the broader series of DIRECT PLUS Brain MRI trials examining how dietary changes, particularly those associated with the Green-MED diet, impact brain aging.  

The DIRECT PLUS project is one of the longest and largest brain MRI studies conducted to date, involving around 300 participants divided into three dietary groups: healthy dietary guidelines; MED; and Green-MED diet.

While further research is needed to fully understand the mechanisms at play, the latest results reinforce a hypothesis that dietary adjustments reduce the risk of age-related cognitive decline.

The DIRECT PLUS project was funded by grants from the German Research Foundation, Israel Ministry of Health, Israel Ministry of Science and Technology, and the California Walnuts Commission.