Researchers from Aarhus University in Denmark found that growing up near vegetation is associated with an up to 55 percent lower risk of mental health disorders in adulthood. Kristine Engemann, the biologist who led the study, combined decades of satellite imagery with extensive health and demographic data of the Danish population to investigate the mental health effects of growing up near greenery.
The study used a large database of Danish citizens along with satellite mapping to measure the correlation between greenery and mental health.
Created in 1968, the Danish Civil Registration System assigns a personal identification number to every Danish citizen and records gender, place of birth and parents’ PINs. A PIN links individuals across multiple databases, including mental health records, and is updated with changes of residence. The researchers’ final data set comprised nearly 1 million Danes who were born between 1985 and 2003 and for whom they had longitudinal records of mental health, socioeconomic status and place of residence.
Satellite data extending back to 1985 allowed the researchers to calculate vegetation density around each residence.
Using these data sources, the researchers compared the risk of developing 16 different mental health disorders in adulthood with how much green space surrounded each child’s residence. And because they had yearly income, work history, and education level, the researchers could weigh the relative contribution of green space against socioeconomics of the parents and neighborhood.
After accounting for those potential confounding factors, the researchers found that growing up near green space was associated with a lower risk of developing psychiatric illness in adulthood by anywhere from 15 percent to 55 percent, depending on the specific illness.
Engemann cautions that the study does have limitations: “It’s purely correlational, so we can’t definitively say that growing up near green space reduces risk of mental illness.” Establishing cause and effect for variables like these is incredibly difficult, according to Engemann.
Despite this limitation, Kelly Lambert, a neuroscientist at the University of Richmond claims that “the effect is remarkable. If we were talking about a new medicine that had this kind of effect the buzz would be huge, but these results suggest that being able to go for a walk in the park as a kid is just as impactful.”
In a related story in Science, Florence Williams, author of The Nature Fix. notes that science has shown that, although we think we like nature, we undervalue how much it helps us—how good it makes us feel. There seems to be a dose curve for nature: For the most part, the more time you spend in a nature environment, the better you’re going to feel.
- If you have kids, the most important thing you can do is get your kids outside often enough to develop their love for nature. You will be giving them a gift they will have their entire lives.
- For adults, go outside more often than you think you want to. Currently, we are outside only an average of five percent each day. You will reap the rewards in increased mood and increased social connection in your relationships.
As I sit here writing this and listening to the wind howl and see that the wind chill is currently 12 degrees, it’s hard to get motivated to go outside in such conditions. But as Williams recommends, we need to be outside more than we think we want to, and I’m sure my percentage is likely lower than the five percent national average.
So maybe it’s time for me to put my big boy pants on and go for a walk outside.
And even if I don’t see immediate improvements in my mood and social connections, I’m sure I’ll reward myself for such good behavior with an Orea cookie or two when I return from my walk.
*image from PeakPx