If 10,000 steps a day has always felt out of reach, here's some good news: the number that matters for your brain may be a lot lower. National coverage this week of a Nature Medicine study says walking about 3,000 steps a day may help protect against Alzheimer's disease. The University flagged the piece because one of the experts interviewed is Benjamin Rosenstein, an assistant professor at the University of Minnesota Medical School.
The research isn't brand new. It was published in Nature Medicine in November 2025, and the lead author was Wai-Ying Wendy Yau of Mass General Brigham's Department of Neurology. Researchers followed 296 adults ages 50 to 90 in the Harvard Aging Brain Study. All of them were cognitively unimpaired when the study began, and they were followed for 2 to 14 years, about 9.3 years on average. The team tracked daily steps with pedometers and watched brain changes with PET imaging.
The results are striking. Among people who already had elevated amyloid in their brains, walking 3,000 to 5,000 steps a day was associated with cognitive decline arriving about 3 years later. At 5,000 to 7,500 steps, the delay was about 7 years. The researchers found the benefit seemed to come mostly from slower buildup of tau rather than from any change in amyloid. "Every step counts — and even small increases in daily activities can build over time to create sustained changes in habit and health," Yau said.
The study also has real limits. Participants were mostly white and highly educated. The pedometers counted steps but didn't measure walking speed or exercise that doesn't involve steps.
That's where Rosenstein comes in. "Movement is an important way to protect your brain health," he said. He also recommended eating patterns like the MIND or DASH diets alongside staying active. He's a natural choice to ask about this. A 2017 graduate of the U's Medical School, he trained in family medicine through the University of Minnesota St. John's Hospital residency and then did a geriatrics fellowship at the University of Wisconsin. He now sees older patients at M Health Fairview Geriatrics on University Avenue in St. Paul and at the Phalen Village clinic.
The practical takeaway is simple. For anyone worried about their own brain, or a parent's, getting to roughly 3,000 steps a day is a modest target.
