You probably knew that, but the excellent Florence Williams details just how good in this artfully done NatGeo feature:
In England researchers from the University of Exeter Medical School recently analyzed mental health data from 10,000 city dwellers and used high-resolution mapping to track where the subjects had lived over 18 years. They found that people living near more green space reported less mental distress, even after adjusting for income, education, and employment (all of which are also correlated with health). In 2009 a team of Dutch researchers found a lower incidence of 15 diseases—including depression, anxiety, heart disease, diabetes, asthma, and migraines—in people who lived within about a half mile of green space. And in 2015 an international team overlaid health questionnaire responses from more than 31,000 Toronto residents onto a map of the city, block by block. Those living on blocks with more trees showed a boost in heart and metabolic health equivalent to what one would experience from a $20,000 gain in income. Lower mortality and fewer stress hormones circulating in the blood have also been connected to living close to green space.
It’s difficult to tell from these kinds of studies why people feel better. Is it the fresh air? Do certain colors or fractal shapes trigger neurochemicals in our visual cortex? Or is it just that people in greener neighborhoods use the parks to exercise more? That’s what Richard Mitchell, an epidemiologist at the University of Glasgow in Scotland, thought at first. “I was skeptical,” he says. But then he did a large study that found less death and disease in people who lived near parks or other green space—even if they didn’t use them. “Our own studies plus others show these restorative effects whether you’ve gone for walks or not,” Mitchell says. Moreover, the lowest income people seemed to gain the most: In the city, Mitchell found, being close to nature is a social leveler.
Read the whole thing here. Then go for a walk outside.
The Earthist Chronicles 
Thank you so much for sharing a link that finally opens the entire article, Tim! I’ve been trying to read it for a month and was thwarted by subscription requirements every time. You (and NatGeo) have just convinced me to make a point of getting out more often. Thank you!
Totally agree with the title! Great post.