Long-Term Air Pollution Exposure Raises Dementia Risk Globally

Recent comprehensive research, including a systematic review and meta-analysis led by the University of Cambridge and published in The Lancet Planetary Health, confirms that long-term exposure to certain air pollutants significantly increases the risk of developing dementia. The study analyzed 51 studies covering over 29 million participants and identified fine particulate matter (PM2.5), nitrogen dioxide, and soot as key pollutants linked to dementia risk, with each 10 μg/m³ increase in PM2.5 raising dementia risk by 17%. These pollutants primarily originate from vehicle exhaust, power plants, and burning wood, and their levels in major UK cities have approached or exceeded the thresholds associated with increased risk. Experts emphasize that air pollution likely contributes to dementia through inflammation and oxidative stress in the brain, suggesting that urban planning, transport policies, and environmental regulations should be integral to dementia prevention strategies. While the exact mechanisms remain under investigation, this evidence strengthens calls for cleaner air policies to protect brain health and reduce the burden of dementia worldwide. The findings highlight the importance of interdisciplinary approaches to mitigate air pollution and its associated health impacts.