Most of us appreciate how good it feels to be immersed in nature, whether it be a stroll in public park, a quiet moment in our backyard, an outdoor camping trip, or a hike through a picturesque landscape; but what does this really do for our health? Is time spent in nature nothing more than a good feel, or is there something about nature that offers us more substantial and longer lasting health benefits? If so, how much time spent in nature do we actually need?
With more and more emerging evidence suggesting significant physical and mental health benefits from immersing ourselves in nature, some doctors are now advocating for prescribing nature visits during the routine delivery of healthcare to improve clinical outcomes (see https://parkrxamerica.org/about.php).
What's more, a recent study led by the European Centre for Environment & Human Health at the University of Exeter found that those who spend two hours a week in natural environments are far more likely to report good health and high wellbeing than those who don't. In this 'exposure-response' observational study of nearly 20,000 participants, the authors controlled for residential greenspaces and potential confounders based on age, sex, socioeconomic status, health status, employment status, education, relationship status and physical activity and found that those who had contact with nature for at least 120 mins in the last 7 days were far more likely to report good health and wellbeing. The beneficial effects of nature immersion peak between 200 - 300 minutes (or 3 to 5 hours).
While this is not an example of an interventional study (which is normally better designed to determine cause and effect), health guidelines have previously been developed based on similarly designed studies to determine the optimal type and duration of physical activity to optimise health outcomes (see https://www.ahajournals.org).
Furthermore, an increasing body of epidemiological evidence suggests that greater exposure to natural environments such as beaches, forests and parks is associated with improved health and wellbeing for those living in urbanised societies. Evidence indicates that exposure to nature is associated with lower risk of mental distress, and is protective against physical conditions such as obesity, cardiovascular disease, diabetes, and hospitalisation from asthma, as well as reduced overall mortality.
Sources:
https://parkrxamerica.org/about.php
https://www.nature.com/articles/s41598-019-44097-3
https://e360.yale.edu/features/ecopsychology-how-immersion-in-nature-benefits-your-health