Working Out Regularly Could Lower Your Risk of Dementia, Study Finds

Your morning run might be pulling double duty for your health. Of course, it’s good for your heart, but it also might protect you from dementia.

A groundbreaking study exploring the relationship between exercise and insulin in the brain suggests regular physical exercise can improve brain function, possibly lowering the risk of dementia.

Dementia, a term for several diseases that impair memory and cognition, is currently the seventh leading cause of death worldwide. Every year, around 10 million new cases of dementia are diagnosed globally—one every 3 seconds. Along with age, factors like high blood pressure and high blood sugar have been found to increase the likelihood of developing dementia.

Think of your muscles like a dry sponge, said Steven K. Malin, PhD, one of the study researchers at Rutgers University. If you don’t exercise, your muscles become rigid, making it harder for insulin to do its job. But when you do move, you’re squeezing and softening that sponge, making the body more responsive to insulin, he said.

So, finding ways to reduce insulin resistance in the body may be a way to prevent dementia.

Why Is Exercise Linked To a Lower Risk of Dementia?

The study found that exercise helps the brain regulate insulin, directly improving cognitive function. Researchers followed 21 older adults with prediabetes who completed 12 supervised moderate to high-intensity exercise sessions over two weeks.

The first-of-its-kind finding pointed to a significant increase in brain-derived extracellular vesicles that carry insulin-related proteins. These tiny messengers help neurons communicate and play a crucial role in maintaining the brain.

Malin said that Akt, a protein believed to be a major player in insulin signaling, has big implications for neuronal cell growth and health.

A poor response to insulin can lead to dementia, so the idea that exercise can help prevent this by possibly boosting insulin signaling is significant, Malin said. While more research is needed, these findings reinforce the idea that physical activity could be an accessible, low-cost way to support long-term brain health.

In the next phase of the study, researchers will use an insulin spray and MRIs to better understand how insulin affects brain function, said Malin. They’ll look at the blood flow in the brain before and after the insulin spray is administered to gain insight into the effect.

Why Are Insulin and Exercise Important for Brain Health?

Insulin is a hormone produced by the pancreas and is best known for regulating blood sugar. But its role in brain health is just as vital. Because the brain is rich with insulin receptors, when insulin binds to them, it helps neurons communicate and strengthens synaptic connections—both of which help support memory and learning.

Poor insulin signaling, as seen in conditions like type 2 diabetes, makes the brain more vulnerable to cognitive decline. Studies suggest insulin resistance contributed to the build-up of amyloid-beta plaques and tau tangles, which are key characteristics of Alzheimer’s disease. Improving insulin sensitivity could help slow down or even prevent these brain changes.

“We’ve known for some time that exercise, particularly aerobic exercise, has a beneficial effect on overall brain health.” Jessica Langbaum, PhD, senior director of Research Strategy at Banner Alzheimer’s Institute, told Verywell. Previous studies have found that exercise can improve or maintain memory and thinking ability in adults.

Langbaum said other ways to boost brain health include staying socially engaged, challenging your mind, getting restful sleep, stress management, a healthy diet, staying active, and managing diabetes and blood pressure.

“The future of dementia prevention will likely include a combination of lifestyle interventions, such as exercise, and medications, to have the most profound effect,” Langbaum added.