3 Thousand Steps a Day May Slow Alzheimer's-Related Brain Changes

New findings suggest that walking just 3 thousand steps a day may help slow the progression of brain changes linked to Alzheimer's disease. Scientists found that physical activity reduced the buildup of harmful tau proteins.

What did the study find?

In the study in the US, 300 older adults were tracked with pedometers for 9 to 11 years. Most participants were white and well educated; the relatively small size of the group matters when interpreting the results.

Physical activity did not reduce the toxic amyloid plaques targeted by Alzheimer's treatments. However, in people who already had these plaques, the buildup of misfolded tau proteins fell in certain brain regions. Tau is a molecule that keeps the inner skeleton of nerve cells stable and supports transport within cells. Its misfolded form appears later in the disease and is more closely tied to cognitive and functional decline. In more active participants, these dementia symptoms dropped by nearly half.

The benefit appeared at 3 thousand steps, roughly half an hour of moderate-paced walking. The strongest effects were seen between 5 thousand and 7 thousand 500 steps. More steps did not always mean more protection, suggesting this may be a more realistic goal than the often-cited 10 thousand steps for older, inactive people.

Studies in the United Kingdom

In a UK study of 1.139 people aged 50 and over, those who were moderately to highly active saw their dementia risk fall by 34 to 50 percent over roughly 10 years. In a larger 2022 study, 78 thousand 430 people were followed for 7 years using wrist-worn accelerometers. 3 thousand 800 steps a day cut dementia risk by 25 percent, rising to 50 percent at 9 thousand 800 steps.

Inactivity speeds up memory loss and creates a vicious cycle. Early signs such as hearing loss can affect self-esteem and reduce physical activity, worsening cognitive decline further. In another study of 15 people with mild to moderate Alzheimer's, those who did Nordic walking with poles had preserved brain function over 24 weeks, with improvement in some functions.