Associations between nature exposure and health: A review of the evidence

Jimenez, M. P., DeVille, N. V., Elliott, E. G., Schiff, J. E., Wilt, G. E., Hart, J. E., & James, P. (2021). Associations between nature exposure and health: A review of the evidence. International Journal of Environmental Research and Public Health , 18(9). https://doi.org/10.3390/ijerph18094790

Nature is connected to a wide array of health benefits for children and youthAlthough research examining the effect of exposure to nature on health outcomes has grown in recent years, studies have mainly focused on adults rather than children. This review synthesizes current research on the relationship between nature and physical and mental health among the general population, while emphasizing the available studies of children and youth.

Researchers conducted a narrative review that aimed to summarize the results of quantitative studies. An academic database was utilized to search for studies published between 2010 and 2020 that focused on engagement with green space and health outcomes. The review was limited to research published in English and included both experimental and observational studies. Studies conducted with children (younger than 10 years) and youth (10-24 years) were included in the review. Reviewed studies were primarily conducted in Western countries. Included studies involved different approaches to nature engagement, such as: “active engagement in the natural environment (e.g., walking, running, or other activities), passive engagement (e.g., resting outside or living with a view), or virtual exposure to nature (e.g., watching videos or viewing images of nature).”

Results suggest that time in nature is linked with mental well-being, overall health, and cognitive development for children and youth. Experimental studies that examined the influence of natural environments reported reduced stress and blood pressure, improvement in cognitive function (attention and executive function), and enhanced pre-frontal cortex brain activity, which drives emotional regulation. Observational studies found that exposure to nature was linked with increased levels of physical activity and decreased BMI, although findings around obesity were mixed. Mental health outcomes associated with nature engagement found by observational studies included reported higher quality of life, improved mood, lower perceived stress, lower risk of depression and psychiatric disorders, improvement in emotional and behavioral problems, and decreased ADHD symptoms. Greenness was associated with decreased risk of low infant birth weight, with stronger effects documented among low socioeconomic status populations. The review also highlights evidence that suggests exposure to nature disproportionately benefits disadvantaged groups, known as the equigenic effect. According to one study in the review, “populations exposed to the greenest environments also had the lowest levels of health inequality related to income deprivation, suggesting that green space might be an important factor in reducing socioeconomic health disparities.”

The review provides substantial evidence that “nearby nature” is associated with a wide array of measurable health benefits, related to both mental and physical well-being of children and youth. The review draws attention to the lack of studies focused on children and youth and calls for further research to investigate nature’s role during these key developmental stages using rigorous study methods. Future research should also strive to resolve inconsistencies in defining nature and in the methods used to quantify exposure to nature. Nonetheless, findings support the implementation of policies aimed at increasing green space access to promote beneficial public health outcomes.

The Bottom Line

Nature is connected to a wide array of health benefits for children and youth