A new study found that diabetes was associated with a 51% increased risk of dementia but exercise was associated with a dose-dependent decrease.
Exercise 3‐5 days/week was associated with a 37% lower dementia risk and >5 days/week was linked to a 59% lower risk of dementia (compared to on exercise).
This was an observational study which means causation cannot be established. However, meta-analyses of randomized controlled trials have found the benefits of regular exercise on cognitive function. The dose-dependent effect on lower dementia risk also strengthens the data.