Fresh air, parks, and green streets are not only pleasant — they may be a true lifeline for the brain, researchers have found.

A new study, published in the journal Scientific Reports, showed that the more greenery a city has, the less harmful the effects of air pollution — and the lower the risk of developing dementia.

Scientists from the University of North Carolina and Harvard analyzed data from nearly 13,000 people over the age of 60. They found that high levels of air pollution were directly linked to an increased risk of Alzheimer’s disease and other forms of dementia. Surprisingly, however, the presence of green spaces significantly reduced this harm.

The exact mechanism is still not fully understood, but the researchers believe that trees and plants not only clean the air but also reduce stress, lower blood pressure, and support mental well-being — all of which are important for brain health.

This study provides yet another strong argument in favor of urban greening. In cities with more parks and tree-lined streets, life is not only more pleasant — it’s also safer to grow old, the scientists emphasize.

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