The study of more than 8,000 people also shows that air pollution is associated with a decrease in brain volume and health. “This study shows that air pollution is associated with worse brain health, including white matter lesions, which are linked with increased risk of stroke and neurodegenerative disease,” says Melissa Furlong, an assistant professor in the University of Arizona Mel and Enid Zuckerman College of Public Health. “We observed that the benefits of physical activity on white matter lesions in the brain significantly diminished as air pollution increased, so that there was no benefit of physical activity on these white matter lesions for people in areas with the highest levels of air pollution. This new analysis underscores the importance of re-evaluating emissions standards, since even low levels of air pollution can affect the brain.” Previous studies have shown that physical activity is associated with a reduced risk of dementia …