“The results of our experiment suggest that the large urban parks
(more than 5 hectares) and large urban woodlands have positive well-
being effects on urban inhabitants, and in particular for healthy
middle-aged women,” the study concluded, as published in the
Journal of Environmental Psychology. The results supported the
earlier five-hours-a-month recommendation. But the researchers also
noted the dose-response relationship: the more nature, the better you
feel. To elevate mood and stave off depression most reliably,
Tyrväinen told me, “five hours per month is the lowest amount of
time to get the effect, then after, if you can go for ten hours, you will
reach a new level of feeling better and better.”
I did some quick calculations. Five hours per month means getting
out there in the verdure a couple of times a week for about thirty
minutes. To achieve ten hours a month requires spending about thirty
minutes in nature five days per week. Or, as one of Tryväinen’s
colleagues told me, “two to three days per month outside the city
would bring the same effect.” No wonder country houses are so
popular; the Finnish nervous system needs them. The Finnish-
approved nature cure won’t work for everyone, because these results
reflect averages. But in a country with a high proportion of mildly
depressed people, if it works for even a small percentage it will
translate into huge savings for the national health-care system.
And in Finland, parks and woodlands are an easy solution. “Nature
here is cheap and free for everyone,” said Tryväinen.
IF TYRVÄINEN IS interested in valuing forests for the sake of the Finnish
economy, one of her collaborators, Kalevi Korpela, is motivated by a
desire to boost the dark Nordic psyche. The Finnish word for healthy,
terve, derives from the word for “hardy pine,” able to withstand
storms. Finns withstand a lot: long, dark winters, freezing
temperatures, a collective historic memory of being regularly invaded
and colonized by Swedes and Russians. From the Swedes, they