The body trait that keeps your brain young

Maintaining more muscle and less hidden belly fat could be key to keeping your brain biologically younger (Washington University). Researchers found that people with a lower visceral fat-to-muscle ratio had brains that appeared structurally younger on MRI scans, while excess deep abdominal fat accelerated brain aging.

“Healthier bodies with more muscle mass and less hidden belly fat are more likely to have healthier, youthful brains,” said Dr. Cyrus Raji, senior author and associate professor of radiology and neurology at Washington University School of Medicine. “Better brain health, in turn, lowers the risk for future brain diseases, such as Alzheimer’s.”

The study, to be presented at the annual meeting of the Radiological Society of North America (RSNA), analyzed 1,164 healthy adults using whole-body and brain MRI scans. Participants’ average age was 55, and the scans highlighted muscle, fat, and brain tissue. Researchers measured total muscle volume, visceral fat (deep belly fat), subcutaneous fat (under the skin), and predicted brain age. The results showed a clear pattern:

More muscle: younger-looking brains

Higher visceral fat-to-muscle ratio: older-looking brains

Subcutaneous fat had no meaningful effect

“Muscle and fat mass quantified in the body are key reflectors of brain health,” Dr. Raji explained.

This shows that how we maintain our bodies can directly relate to how our brains age.

Implications for Health and Prevention

The findings suggest that building muscle and reducing visceral fat are actionable goals for long-term brain health. While common weight-loss medications like GLP-1 drugs (e.g., Ozempic) can reduce body fat, they may also contribute to muscle loss.

“Losing fat, especially visceral fat, while preserving muscle volume would have the best benefit on brain aging and brain health,” Dr. Raji said.

Our work can guide the development of future therapies and inform dosing strategies to protect both body and brain.

Whole-body MRI and AI-based brain age estimates could provide measurable benchmarks for lifestyle or medical interventions aimed at protecting cognitive function.

More than just a number on a scale, your body composition may be one of the most important factors in maintaining a youthful brain. Strength training, healthy nutrition, and managing hidden abdominal fat aren’t just good for your heart and metabolism, they may also help slow the clock on brain aging.