What the World's Top Dementia Expert Does Every Day to Protect His Brain

If anyone has earned the right to lecture us about brain health, it's Ron Petersen. At 80 years old, he still works full-time, sees patients, and has spent more than half a century figuring out why some minds stay sharp while others fade. His message? You have more control than you think.

"Aging need not be a passive process," Petersen has said. "We can influence it. We can engage. And here's where lifestyle comes into play." Coming from someone with his credentials, that's not a motivational poster — it's a career's worth of evidence distilled into a single idea.

The Man Behind the Science

For more than 50 years, Petersen has studied healthy aging, cognition, and dementia. His research established the concept of mild cognitive impairment — the critical zone that lies between healthy cognitive aging and dementia. That distinction matters enormously. It gave doctors and scientists a framework for catching decline early, before it becomes something much harder to manage.

Petersen has co-written over 1,500 peer-reviewed articles and works full-time in clinical research as the director of the Mayo Clinic Study of Aging, where he also sees patients. He recently received a lifetime contribution award from the National Academy of Neuropsychology. And yet, when asked what he personally does to keep his own brain healthy, his answers are refreshingly ordinary.

Move Your Body — That's the Big One

Ask Petersen to name the single most important thing a person can do for their brain, and he doesn't hesitate. If somebody pushed him to the wall and demanded just one thing, his answer would be exercise. Not supplements. Not brain games. Exercise.

When he isn't traveling, he exercises about three to four days a week, often with his wife at a health club. He does brisk walking, treadmill intervals at varying speeds, and also plays golf and does resistance training — including leg presses, upper body presses, and flexibility exercises. His work and subsequent research have found that exercise can slow cognitive decline, reduce Alzheimer's risk, and promote better brain health.

Petersen recommends 150 minutes of aerobic exercise a week. Even a little bit — such as 10 minutes of super-slow jogging — helps, research shows. "Just doing more than you're doing now is probably the single best item," he said. That's a low bar. A deliberately low one.

Eat Well, Sleep Better, Keep Thinking

Petersen says it's hard to know whether a particular diet is better than another for the brain, but eating a heart-healthy diet — such as the Mediterranean diet or MIND diet — is a good idea. Studies have shown that focusing on foods such as vegetables, nuts, beans, fruit, and seafood may cut the risk of cognitive decline and dementia, particularly in people already at higher risk. He often eats granola and yogurt with berries for breakfast. Lunch is "on-the-fly," but he sometimes has fruit, yogurt, and granola then too. He doesn't eat a lot of red meat — about once every two weeks.

Sleep becomes more difficult as we age. "Usually what happens is the quantity increases and the quality decreases," Petersen said. "So we may spend more time in bed but we're awakened and we can't get back to sleep." Sleep is important for strengthening memories and clearing out waste from the brain. On the intellectual side, activities ranging from reading the newspaper to going to lectures or discussing things with others can benefit brain health — and Petersen recommends finding one "that's fun, that you enjoy doing and look forward to doing each day."

A Reassuring Blueprint for Anyone Worried About Aging

What makes Petersen's approach compelling isn't that it's radical — it's that it isn't. No expensive interventions, no extreme regimens. Walk more. Sleep well. Eat real food. Stay curious. Stay connected. Petersen says you can't prevent dementia, but you can reduce some of your dementia risks — and in fact, there are a dozen risk factors that are modifiable.

The broader takeaway is that brain health isn't a single dramatic decision — it's the accumulation of small, consistent ones made over decades. Petersen has spent 50 years studying what goes wrong in the aging brain. The fact that his personal playbook looks a lot like common sense isn't a disappointment. It's the whole point. The science, it turns out, keeps pointing back to the basics — and at 80, he's living proof that they work.