• Posted December 3, 2024

Maintain Muscle as You Age to Keep Brain Sharp

Maintaining muscle might be one way to help prevent dementia, new research suggests.

“We found that older adults with smaller skeletal muscles are about 60% more likely to develop dementia when adjusted for other known risk factors,” said study co-senior author Marilyn Albert. She's a professor of neurology at Johns Hopkins University School of Medicine in Baltimore.

Her team presented its findings Tuesday in Chicago at the annual meeting of the Radiological Society of North America.

As the researchers explained, skeletal muscle makes up about a third of a person's body weight and does tend to shrink with age.

To find out how muscle loss might impact brain health, Albert and colleagues focused on the temporalis muscle, which helps move the jaw.

It's been long known that reductions in this muscle reflect a loss of skeletal muscle throughout the body.

“Measuring temporalis muscle size as a potential indicator for generalized skeletal muscle status offers an opportunity for skeletal muscle quantification," lead author Dr. Kamyar Moradi said in a meeting news release. He's a postdoctoral research fellow in radiology at Hopkins.

The research team was able to gauge the size of the head's temporalis muscle by looking at brain scans of 619 people who averaged 77 years of age.

Folks were divided into two groups: Those with larger temporalis muscles and those with smaller ones.

Having a smaller temporalis (and, by extension, smaller skeletal muscles throughout the body) was tied to a significantly higher likelihood that the person was also diagnosed with Alzheimer's disease, the study found.

Smaller temporalis muscles were also linked to a higher risk for memory issues, declines in "functional activity," and shrinking brain volume, the researchers found.

The study wasn't designed to prove cause-and-effect, only that reductions in skeletal muscle are associated with dementia. And because these findings were presented at a medical meeting, they should be considered preliminary until published in a peer-reviewed journal.

But study co-senior author Dr. Shadpour Demehri, a professor of radiology at Hopkins, said that once a person knows that they're losing vital muscle, they can use weight-training, diet and other means to slow that loss.

“These interventions may help prevent or slow down muscle loss and subsequently reduce the risk of cognitive decline and dementia,” Demehri said.

More information

Find out more about preventing Alzheimer's disease at the U.S. National Institute on Aging.

SOURCE: Radiological Society of North America, news release, Dec. 3, 2024