A study published in 2017 by Cox and colleagues, reported remarkable multiple health benefits of nearby nature, such as having a private garden or the amount of neighborhood vegetation cover. The study surveyed 1,023 adults living in Southern England during the month of May. Dose-response analyses accounted for the type of nature, frequency, duration, and intensity of nature experiences associated with health outcomes for depression, physical and social health, physical behavior, and nature orientation. While the study did not find a relationship between nature exposure and self-reported physical health, four health outcomes measures including depression, perception of social cohesion, physical activity, and nature orientation all improved as the frequency and duration of nature exposure increased. Higher intensity levels of nature exposure were also associated with reductions in depression. Dose responses of at least one garden visit per week or a neighborhood vegetation coverage of 25% or more appeared sufficient to lower levels of depression. Between 4-5 garden visits per week, or living in a neighborhood with greater than 35% vegetation coverage provided optimal depression reduction. The authors conclude that city residents having a tree cover of at least 15% and spending from 10 minutes up to five hours in a garden may reduce the number of individuals with depression by 5 to 27%.
Cox, D.T.C., Shanahan, D.F., Hudson, H.L., Fuller, R.A., Anderson, K., Hancock, S., Gaston, K.J. (2017) Doses of nearby nature simultaneously associated with multiple health benefits. International Journal of Environmental Research and Public Health. 14(2), 172; doi:10.3390/ijerph14020172.
Charlie Guy, Professor, UF Department of Environmental Horticulture