• Posted March 15, 2024

Eating Healthy Slows 'Aging Clock,' Helping to Shield Your Brain From Dementia

Scientists have long noticed that folks who eat healthy have healthier brains as they age, including lowered odds for dementia.

Now, researchers believe they know why: Regimens like the heart-healthy Mediterranean or DASH diets appear to slow biological aging, helping to protect the brain.

"Our findings suggest that slower pace of aging mediates part of the relationship of healthy diet with reduced dementia risk," said study first author Aline Thomas. She's a postdoctoral researcher at Columbia University's Taub Institute for Research on Alzheimer's Disease and the Aging Brain, in New York City.

The findings were published recently in the Annals of Neurology.

In the study, Thomas and her colleagues examined decades of data from the ongoing Framingham Heart Study, which began in 1971.

The researchers honed in on over 1,600 people in the second generation of the study, which had people check in every four to seven years with data on (among other things) their diets and the results of neuro-cognitive tests.

A total of 160 of the participants went on to develop dementia.

"Much attention to nutrition in dementia research focuses on the way specific nutrients affect the brain,"said study senior author Daniel Belsky, an associate professor of epidemiology at the Columbia School of Public Health and the Columbia Aging Center.

"We tested the hypothesis that healthy diet protects against dementia by slowing down the body's overall pace of biological aging," Belsky explained in a Columbia news release.

The researchers were able to track cellular aging in participants using an "epigenetic clock" called DunedinPACE. It was developed by Belsky and other researchers while he was at Duke University.

According to Belsky, DunedinPACE is "like a speedometer for the biological processes of aging," tracking them as they work on the body over time.

The study found that folks who most closely adhered to what is called the Mediterranean-Dash Intervention for Neurodegenerative Delay (MIND) diet had slower aging, as measured by DunedinPACE, as well as lowered odds for dementia and early death.

Overall, they calculated that about 27% of the association between a healthy diet and lowered dementia risk is probably due to slowed aging.

The MIND diet combines elements of both the Mediterranean and DASH diets, long recommended by nutritionists and other experts in health. It relies on lots of whole grains, vegetables, nuts, beans, leafy greens, fish and lean meats. It avoids red meat, sugary foods and foods high in saturated and trans fats.

Despite the findings, Thomas said there's still much to learn about healthy living's connection to brain health.

"A portion of the diet-dementia association remains unexplained, therefore we believe that continued investigation of brain-specific mechanisms in well-designed mediation studies is warranted," she said.

More information

Find out more about the Mediterranean Diet at the Cleveland Clinic.

SOURCE: Columbia University, news release, March 14, 2024