Just 3,000 steps a day may slow Alzheimer’s progression, study finds
Walking as few as 3,000 steps a day could slow the progression of Alzheimer’s disease in at-risk older adults, delaying cognitive decline by up to seven years, new researh has found.
A 14-year study has found that even modest physical activity appears to protect against the brain changes and decline linked to the condition.
Researchers tracked 296 people aged 50 to 90 who were cognitively healthy at the start, recording their daily step counts alongside annual memory tests and brain scans.
The team at Mass General Brigham hospital in Boston used PET scans to measure amyloid-beta plaques and tau tangles – toxic proteins that build up in the brain and drive Alzheimer’s progression.
Among participants with high amyloid levels at baseline – signalling greater Alzheimer’s risk – those walking 3,000 to 5,000 steps a day showed cognitive decline delayed by about three years.
Those reaching 5,000 to 7,000 steps saw delays of roughly seven years.
“We’re encouraging older people who are at risk of Alzheimer’s to consider making small changes to their activity levels, to build sustained habits that protect or benefit their brain and cognitive health,” said Dr Wai-Ying Yau, the study’s first author.
In contrast, sedentary participants with high amyloid levels experienced faster tau buildup and cognitive decline. Those with low amyloid at the start showed little decline or tau increase regardless of activity levels.
Dementia affects around 50 million people worldwide, with Alzheimer’s the most common cause. In the UK, more than 500,000 people live with the condition.
While the researchers note they cannot fully rule out reverse causation – where early, unseen brain changes cause people to walk less – the findings suggest physical activity is protective.
“We need randomised clinical trials to prove cause and effect, but it’s very encouraging that physical activity may help to modify someone’s trajectory,” said Yau.
“If they have amyloid, they could have a slower rate of decline if they’re more physically active.”
The biological reasons remain unclear, but physical activity is known to boost blood flow, reduce inflammation and trigger hormones and growth factors that support brain health.
“In terms of potential mechanisms, that is the million-dollar question we want to look at in future studies,” Yau added.
Dr Julia Dudley, of Alzheimer’s Research UK, said: “The findings suggest that even a modest amount of walking each day, around 5,000 steps, is linked to a slower buildup of tau protein in the brain, one of the key drivers of Alzheimer’s disease.
“This gives us a clearer picture of how everyday activity may support brain health and impact the underlying causes of Alzheimer’s.
“More research, including clinical trials, is needed to see the direct impact of physical activity on preventing and slowing the progression of dementia and on underlying disease causes.
“But studies like this reinforce that simple changes to our lifestyle could help keep our brains healthier for longer.”
The findings challenge the 10,000-step target, suggesting that smaller, more achievable goals may still bring significant benefits for people at risk of Alzheimer’s disease.
