How might contact with nature promote human health? Promising mechanisms and a possible central pathway

Abstract

How might contact with nature promote human health? Myriad studies have linked the two; at this time the task of identifying the mechanisms underlying this link is paramount. This article offers: (1) a compilation of plausible pathways between nature and health; (2) criteria for identifying a possible central pathway; and (3) one promising candidate for a central pathway. The 21 pathways identified here include environmental factors, physiological and psychological states, and behaviors or conditions, each of which has been empirically tied to nature and has implications for specific physical and mental health outcomes. While each is likely to contribute to nature’s impacts on health to some degree and under some circumstances, this paper explores the possibility of a central pathway by proposing criteria for identifying such a pathway and illustrating their use. A particular pathway is more likely to be central if it can account for the size of nature’s impacts on health, account for nature’s specific health outcomes, and subsume other pathways. By these criteria, enhanced immune functioning emerges as one promising candidate for a central pathway between nature and health. There may be others.

Green Infrastructure, Green Stormwater Infrastructure, and Human Health: A Review

“…Previous studies have suggested that contact with nature and natural elements improves physical health [5,55,56]. One of the underlying theories is that modern urban life causes stress [57], and chronic stress leads to physical sickness [58].…”

“…Previous research has established that trees provide a wide variety of health benefits [55]. The presence and density of trees has been used to explore such benefits [2,3,65,72].…”

“…First, in Psycho-Evolutionary Theory, we learned that humans evolved around savannah landscapes which combine trees with clear open spaces. Trees provided survival tools to our human ancestors and were their homes; thus, humans can relax and de-stress around well-placed trees [55]. The Reasonable Person Model also posits that people are more likely to be reasonable around the supportive environment; thus, tree density can make people more reasonable and social, leading to fewer violent social interactions [73].…”

Within What Distance Does “Greenness” Best Predict Physical Health? A Systematic Review of Articles with GIS Buffer Analyses

“…Many of the analyses in this review examined health outcomes for which multiple other reviews find consistent ties between greenness and physical health -namely physical activity, birth and developmental outcomes, and cardiovascular outcomes [1,7,[14][15][16]. The analyses in this review represent a relatively small sample of articles using a single analytic tool to estimate residential greenness.…”

“…Physical health outcomes were divided into 18 categories. These were adapted from categories identified in previous greenness and health literature reviews [1,7,8]. The manner of data collection for physical health outcomes was grouped into three categories, based on whether data were objective (i.e., biomarkers, vital signs), expert or clinician diagnoses (i.e., electronic medical records), or subjective (i.e., self-reported health questionnaires).…”