All factors

Air pollution

Fine-particle pollution is linked to higher dementia risk, including at levels common in US cities.

Population risk0.7%
Evidence gradeMeta-analysis

One analysis that pools the results of many studies, so no single odd result can carry the conclusion.

Why it matters

Pollution particles enter the brain through the nose and blood, causing inflammation. HEPA filters and avoiding outdoor exercise on high-pollution days reduce exposure.

What to ask at the checkup

Ask whether air quality is a concern and what steps might reduce exposure

Screening: Local air quality index review

Sources

Ambient air pollution and clinical dementia: systematic review and meta-analysis

Wilker EH, Osman M, Weisskopf MG. BMJ, 2023.

Dirtier air was linked to more dementia, including at levels common in US cities.

Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission

Livingston G, Huntley J, Liu KY et al.. The Lancet, 2024.

Fourteen things people can change account for nearly half of dementia cases at the population level.

Routines for this factor

Run the air purifier today

Turn on the HEPA air purifier in the room where most time is spent.

2 min, difficulty 1/3

Exercise indoors on high-pollution days

Check the air quality index and move exercise indoors if it is above 100.

10 min, difficulty 1/3

This is research information, not medical advice. Nothing here replaces your parent's doctor.