Key points from article :
A new long-term study published in JAMA offers one of the strongest signals yet that staying active in midlife and older adulthood can meaningfully lower the risk of dementia. Led by researchers analysing data from more than 4,000 adults over up to 37 years, the study found that people who were the most physically active between ages 45 and 88 had a 41–45% lower risk of developing dementia or Alzheimer’s disease. Activity earlier in adulthood, however, did not appear to influence later dementia risk, highlighting midlife and beyond as especially important windows for brain protection.
The study measured physical activity across light, moderate, and heavy intensity, and found that even modest late-life movement — such as walking or gentle exercise — was beneficial. Moderate to vigorous activity in midlife offered the strongest protection, particularly for people without the APOE ε4 gene linked to Alzheimer’s. But even those with this genetic risk factor gained measurable benefit in their later years, suggesting that lifestyle choices can buffer inherited vulnerability. While observational, the findings reinforce well-established biological links between exercise and healthy brain ageing, including improved blood flow, reduced inflammation, and strengthened neural connections.
Experts say the results underscore a hopeful message: it’s never too late to start. Regular movement of any kind — brisk walking, cycling, gardening, yoga, or simple at-home exercises — can help preserve memory and cognitive function. The study also fits into a broader picture of dementia prevention, alongside managing cardiovascular health, protecting hearing, maintaining oral health, staying socially engaged, eating a Mediterranean-style diet, stimulating the mind, and prioritising good sleep.
Overall, the research suggests that increasing activity in your 40s, 50s, 60s, or even 70s can deliver meaningful long-term brain benefits. Small, consistent changes matter — and for many people, movement may be one of the most accessible tools for protecting cognitive health as they age.
