Research

Mixed

Low levels of physical activity are associated with a significantly higher risk of incident dementia in older adults (aged 60+), specifically demonstrating a threshold effect where the lowest activity quintile faces increased risk compared to higher activity levels.

Maintain a baseline level of physical activity as you age to protect your brain. This study suggests that even modest activity (moving out of the 'lowest quintile' of inactivity) is protective against dementia, with the strongest benefits seen in those over 75. You do not need to be an elite athlete; simply avoiding a sedentary lifestyle and engaging in regular movement helps preserve brain volume and reduces dementia risk.

GoodSupportsHIGH confidence
Participants in the lowest quintile of PAI had an increased risk of incident dementia compared with those in higher quintiles (hazard ratio [HR] = 1.50, 95% confidence interval [CI] = 1.04–1.97, p = .028) in a multivariable-adjusted model.
Zaldy S. Tan et al. · The Journals of Gerontology Series A · 2016

Why this rating

Large longitudinal cohort (Framingham), long follow-up (10 years), rigorous adjustment for confounders, though observational design limits causal inference.

Source

Physical Activity, Brain Volume, and Dementia Risk: The Framingham Study

Zaldy S. Tan et al. · The Journals of Gerontology Series A · 2016

DOI 10.1093/gerona/glw130

cohort · n=3714Cited 208×
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DOI resolved against Crossref · corpus check 2026-06-10

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