Visiting green spaces deters mental health drug use, researchers find
Visits to parks, community gardens and other urban green spaces may lower city dwellers’ use of drugs for anxiety, insomnia, depression, high blood pressure, and asthma, research has found.
Researchers in Finland found that visiting such areas three to four times a week cuts people’s chances of turning to drugs for mental health problems or high blood pressure by a third, and for asthma by about a quarter.
Moreover, the positive effects of visiting green spaces were stronger among those reporting the lowest annual household income, the researchers found.
The findings correlate with a growing body of evidence that a lack of access to green spaces is linked to a range of health problems. Access tends to be unequal, with poorer communities having fewer opportunities to be in nature.
To investigate the link, researchers from the Finnish Institute for Health and Welfare drew on the responses of 16,000 randomly selected residents of Helsinki, Espoo and Vantaa – three cities that make up the largest urban area in Finland – to the Helsinki capital region environmental health survey in 2015-16.
The survey gathered information on how city dwellers aged at least 25 experienced residential green and blue spaces within a 1km (0.62-mile) radius of their homes. Green areas included forests, gardens, parks, castle parks, cemeteries, zoos, natural grasslands, moors and wetlands; and blue areas included sea, lakes, and rivers.
Respondents were asked to report their use of prescribed drugs for anxiety, insomnia and depression, and for high blood pressure and asthma. They were then asked how often they spent time or exercised outdoors in green spaces, during May and September, with options ranging from never to five or more times a week.
The researchers chose prescription drugs as a proxy for ill health. They picked those for anxiety, insomnia and depression, and high blood pressure and asthma in particular because they are used to treat common but potentially serious health issues.
They found a strong correlation between visits to green spaces and lower odds of using such drugs. Compared with less than one weekly visit, visiting three to four times weekly was associated with 33% lower odds of using mental health drugs, 36% lower odds of using blood pressure drugs, and 26% lower odds of using asthma drugs.
Curiously, however, those who visited green spaces at least five times a week were only 22% less likely to be using mental health drugs, and 24% less likely to be using asthma medications. Increased frequency did however correlate to lower odds of needing blood pressure drugs, with 41% lower probability than someone visiting less than once a week.
“Mounting scientific evidence supporting the health benefits of nature exposure is likely to increase the supply of high-quality green spaces in urban environments and promote their active use,” the researchers wrote. “This might be one way to improve health and welfare in cities.”
Their research is published online in the journal Occupational & Environmental Medicine.