Intuitively, people know nature is good for them, and research backs that up. But what dosage is needed? Recent studies have explored the duration and frequency of time spent in nature that are necessary to yield health benefits. This research, funded by the TKF Foundation, shows that just 10 minutes of exposure to nature, 2-3 times per week, produces mental restoration benefits. And, short nature time-outs can happen in small, urban green spaces or one’s backyard; one need not travel beyond the city to visit big parks or wild places.

The research, conducted by MaryCarol Hunter, a professor at the University of Michigan, and Dr. Marc Berman of the University of Chicago, was recently presented at the ASLA (American Society of Landscape Architects) Annual Meeting. The work is part of a larger body of research being supported by the TKF Foundation, which has awarded grants to six projects across the country that integrate the design of urban spaces with research on user benefits. All seek to prove the health benefits that green spaces, located in urban areas, offer through contemplation and restoration, so as to inform and influence decision-makers in city design and planning.

“Over the past 20 years, we’ve invested in the creation of more than 130 urban green spaces,” said Mary Wyatt, executive director, TKF Foundation. “Hunter’s and Berman’s initial results confirm the significance of this work and our observations over the past two decades. Our goal is to freely share the results of their research – along with findings from our other five studies – to help city-dwellers cope with the stresses of city life and build community cohesion.”

Hunter’s study involved having subjects immerse themselves in nature at least 2.5 times a week for a minimum of 10 minutes, and answer questions before and after about their mental well-being on a specially created mobile app. The digital entries were correlated with participants’ cortisol levels in saliva, an indicator of stress. Looking at the data, Hunter found that just 10 minutes is effective in being in nature to receive its benefits. Participants reported having significantly less stress, an improved ability to focus, and an increased satisfaction with their mood and energy levels. Also, benefits were greater in residential landscapes or small parks.

In Berman’s study, subjects were asked to take a 2.5 mile, 50-minute walk through either a dense, urban environment or an arboretum. Afterward, they were given memory tests to measure their ability to concentrate or focus. Results showed a noticeable difference in those who had walked through the arboretum; they had a 20 percent improvement in working memory over the other group. As confirmation, another study using photos of urban or nature scenes rather than walks yielded similar results.

However, there are still many questions to answer, for example, how senses other than sight might influence health benefits. Both Hunter and Berman are working to discover the specific features of nature – such as naturalness, complexity, form, openness, access and safety – that create a sense of well-being and improve one’s ability to concentrate.

Berman is analyzing the fine grain of scenes to be able to understand how people will respond to what they see in the city. He classifies natural and urban images by brightness, color value, saturation and hue. He is also looking at nature images using grey scale, and measuring curved or straight edges within. Using an equation of such measures, he is able to predict at 80-90 percent accuracy how natural people perceive a scene to be.

Hunter’s research was published in Frontiers in Psychology (Aug. 19, 2015) and Berman’s in the Journal of Experimental Psychology (Sept. 7, 2015). Final results from their studies and TKF Foundation’s other five final grant projects, recipients of TKF’s National Nature Sacred Awards, are being shared as the work is completed and published. For more information, visit www.naturesacred.org.

The TKF Foundation, a private nonprofit, believes that everyone should have access to the benefits of nature and, as such, has funded more than 130 publicly accessible, urban green spaces for more than 20 years. These spaces, called Open Spaces Sacred Places, are meant to reawaken and reaffirm the powerful connection between nature, spirit and human well-being. They were created in partnership with local organizations to increase a sense of community and contribute to a deepening of human connections. Most recently, the TKF Foundation issued its final six grants, which include site creation and groundbreaking research studies across the country that examine the impact of nature on individuals and communities.