Just 3,000 steps a day may help slow Alzheimer's, scientists find
Walking just 3,000 steps a day could help slow Alzheimer’s-related brain changes, according to new research. Scientists discovered that physical activity was linked to less buildup of harmful tau proteins and nearly half the cognitive and functional decline, even in people already showing early signs of the disease. The strongest benefits appeared at 5,000 to 7,500 daily steps, suggesting that the popular…
Key points
- A study of almost 300 older adults found activity reduced tau buildup, not amyloid plaques.
- Benefits appeared at about 3,000 steps daily, with the effect plateauing after 5,000 to 7,500.
- The study was small and mostly white and well-educated, and other lifestyle factors were not counted.
A new study suggests that low levels of physical activity may help protect the brain from Alzheimer's disease, though not in the way researchers expected. Scientists tracked almost 300 older adults with early brain signs of Alzheimer's for nine to 11 years using pedometers.
Physical activity did not reduce the toxic amyloid plaques that most Alzheimer's treatments target. Instead, in people who already had those plaques, activity reduced the buildup of misfolded tau proteins in certain brain areas, and signs of dementia were cut by almost half in more active participants.
How many steps help
Benefits appeared at just 3,000 steps, roughly half an hour of walking at a moderate pace. The optimal range was 5,000 to 7,500 steps daily, after which the effect plateaued, suggesting a realistic target for older, sedentary people rather than the often-cited 10,000 steps.
More steps didn't necessarily mean greater protection
— the article
Limits and other evidence
The study involved a fairly small group of mostly white, well-educated people in the US and did not take other lifestyle or health factors into account. A UK study of 1,139 people over 50 found a 34-50% reduction in dementia risk among those moderately to vigorously active, and a 2022 UK study of 78,430 people found a 25% reduction at 3,800 steps daily, rising to 50% at 9,800.
The article notes that people who walk more also tend to have better cardiovascular health, and that healthy habits often go together, making it hard to say exercise alone is responsible. It also says the relationship may work in reverse, with early symptoms reducing activity.
