The Main Idea

Just 15 minutes outside in nature can make you feel happier and less worried, especially if you live in a city.

Study by Leiden University, edited by Gaby Clark, reviewed by Robert Egan

What the Study Found

Green spaces like parks and trees help people feel better mentally – and this is extra important in busy cities. Scientists from Leiden University and Stanford University did a big study to learn how nature helps people who live in cities feel better. They also found cheap ways to make city life healthier for everyone.

By the year 2050, about 70 out of every 100 people in the world will live in cities. Living in cities can sometimes make people feel anxious or sad. This new study, published in a science magazine called Nature Cities, shows that even spending a short time in nature can help with these feelings. The study gives ideas to city planners and leaders about how to use green spaces to help people feel better mentally. These green spaces also help in other ways, like making the air cooler and cleaning up pollution.

Learning More About Nature and Mental Health

“Other studies have already shown that being in nature helps people feel better,” says Anne Guerry, one of the main scientists who worked on this study. “But most of those studies couldn’t prove that nature actually caused people to feel better, or they only worked in one place, or they didn’t test different types of nature. Our study helps fill in those missing pieces.”

The scientists looked at information from almost 5,900 people across 78 different experiments. All types of city nature helped people feel better, but forests in cities worked the best – especially for helping people feel less depressed and worried.

Young adults got even more benefits from nature, which is important because most mental health problems start before people turn 25. Something interesting they found was that just sitting and resting in green spaces helped reduce bad feelings more than being active, though both sitting and being active made people feel more energetic and alert.

Roy Remme, a scientist from Leiden, says, “Our results show that even spending a short time (less than 15 minutes) in nature can help your mind feel much better. Also, spending longer time in nature (more than 45 minutes) helps even more with reducing stress and making you feel more alive and energetic.”

What Cities Should Do

Based on what they learned, the scientists suggest that cities should not only protect big parks and forests, but also add smaller “pocket parks” and more trees on streets so people can easily find nature throughout the city. Simple changes can help too – like having more windows that look out at trees and plants, creating quiet spots filled with nature, or having community programs like group meditation in parks. These are cheap ways to help everyone in the city feel better mentally.

How This Helps Real People

Yingjie Li, the main scientist on this study, says that doing this research has made his own life better. He walks to work more often now and pays more attention to birds and plants he sees along the way.

“I also tell my friends about this and encourage them to notice how even small moments with nature can make a difference. This work has helped me see that having nature in cities isn’t just good for cities – it’s good for us too.”

More information: The full study is called “Acute mental health benefits of urban nature” and was published in Nature Cities magazine in 2025.

Study provided by Leiden University