As urban planners debate the merits of, say, a new shopping center versus maintaining the local park, they might consider this: over time, parks–and other green spaces–make people feel better about themselves.
Or, at least, that is the takeaway from a long-term study of 12,000 people in the U.K. Researchers at the University of Exeter used survey data measuring both life satisfaction and mental distress, then matched that to a map ranking 32,482 areas for their greenness. They found that people living in greener areas were consistently more satisfied, and experienced less distress.
The work builds on previous studies that also found a green space-mental health link, but had selection issues. Researchers couldn’t say whether it was the green space that made people happier, or whether happy people moved to greener areas. The new work gets around that by following the same people over an 18-year period.
Lead author Mat White says at an individual level the effect isn’t huge, statistically. But it is significant in comparative terms. For example, according to the research, living near a green space has a third of the positive mental effect as getting married, and a tenth of the impact of getting a job when you don’t have one.
Moreover, the effect of green space could be cumulatively large, if you look at the wider population. Getting married might improve two people’s sense of well-being, but a park could improve a whole city’s, potentially. “These small differences can add up if they affect many people,” he says.
For that reason, White suggests planners take mental health into account. “Health outcomes are only one thing in the mix. But I’d say be very careful before building on public green spaces, or cutting budgets to maintain existing ones.”