Several factors influence brain age, including actual (chronological) age, genetics, and lifestyle, says Dafna Pachter, a PhD student at Ben-Gurion University of the Negev in Israel and the study’s first author. “We have ways to influence brain age, and that was the purpose of the trial: to examine how diet affects markers involved in this process.”
By examining changes in certain blood proteins called biomarkers for study participants who followed a green Mediterranean diet over 18 months, researchers observed “in real life how lifestyle and dietary changes affect the aging process,” Pachter says.
“This approach offers a dynamic view of brain health, allowing us to detect biological changes long before symptoms appear. By mapping these protein signatures, we gain valuable insights into how interventions like diet may help maintain cognitive function as we age.”
What Is the Green Mediterranean Diet?
- Large amounts of fruits, vegetables, and whole grains, along with healthy fats from nuts, seeds, and olive oil
- Moderate amounts of dairy, fish, and red wine
- Small amounts of red meat, eggs, processed foods, refined grains, and added sugars
The green Mediterranean diet is a modified version that suggests cutting out or drastically reducing animal products in favor of more plant-based foods, says Martha Theran, RDN, who works at the Pritikin Longevity Center in Miami.
This way of eating “is one of the most powerful tools we have for protecting both heart and brain health,” Theran says.
Green Mediterranean Diet May Slow Brain Aging
To evaluate the effects of diet on brain age, researchers analyzed data from nearly 300 participants in the DIRECT PLUS trial, a long-running study on the link between diet and brain health.
Participants were randomly selected to follow one of three diets over 18 months:
- A standard healthy diet
- A traditional Mediterranean diet with walnuts
- A green Mediterranean diet that was low in red and processed meat and incorporated walnuts, green tea, and an aquatic superfood called Mankai.
MRIs were used to measure brain age. Researchers also measured 87 different protein biomarkers in participants’ blood to see if they “differed among participants with different brain aging trajectories and whether these differences were affected by diet,” Pachter says.
They found that higher levels of two proteins — galectin-9 (Gal-9) and decorin (DCN) — were associated with accelerated brain aging. However, these protein levels decreased over the 18 months in participants who followed a green Mediterranean diet.
“This indicates a potential positive effect on biological processes related to brain aging through blood protein modulation,” says Pachter, adding that the findings “highlight the importance of adopting a healthy dietary pattern, particularly the green Mediterranean diet, rich in polyphenols, as a potential way to protect our brain.”
A Green Mediterranean Diet May Come With Several Health Benefits
Brain aging involves the gradual loss of neurons and shrinking brain tissue, which can lead to cognitive decline and other neurological issues, Pachter says.
“While aging itself cannot be prevented, our study examined how an 18-month dietary intervention might influence these processes,” she says.
“The green Mediterranean diet appears to amplify the benefits of the traditional Mediterranean diet by placing a greater emphasis on polyphenol-rich foods, such as green tea, walnuts, and other plant-based foods,” Theran says. “While the traditional Mediterranean diet is already very healthy, the ‘green’ version fine-tunes it to target brain health more directly.”
The brain-protecting benefits seen in this study suggest that a green Mediterranean diet could be a potential drug-free way to slow age-related brain decline, Theran says.
The Study Has Limitations
The trial primarily included men, Pachter says, “so applicability to women requires confirmation.”
The team used MRIs to determine each participant’s so-called brain age, which provides a “robust biomarker,” Pachter says, but it’s not a clinical diagnosis or direct pre- or post-intervention cognitive measure.
Next, Pachter says her team plans to expand and validate additional variables that could serve as early indicators of increased risks for cognitive decline. She says this may enable intervention before symptoms appear.
Tips for Adopting a Green Mediterranean Diet
To boost the brain-protecting potential of a Mediterranean diet, Theran suggests “greening” your plate with these tips:
- Add one to two cups of green tea to your daily routine.
- Eat a handful of walnuts most days.
- Include more leafy greens and plant proteins, such as lentils, beans, tofu, nuts, Mankai, and other greens.
- Reduce your intake of red and processed meats. Choose fish, poultry, or plant-based proteins instead.
- Get more polyphenols by eating more berries, herbs, olive oil, and green vegetables.
The study results suggest that these small tweaks “can create measurable differences in brain aging markers,” Theran says.
