It's no secret that Americans are stressed, especially in the workplace.
Fifty-two percent of working professionals in the U.S. say their jobs are stressful, according to a 2018 survey from LinkedIn. And stress has been linked to serious health problems such as heart disease, asthma, obesity and diabetes. In fact, the need for stress relief is at least in part behind the current popularity of products with CBD, a cannabis compound that some claim has a calming effect.
But the real key to reducing stress may actually be free, easy and available to everyone: Just 20 minutes of contact with nature significantly lowers stress hormone levels, according to a new study published in the journal Frontiers in Psychology.
For the study, participants were asked to take a "nature pill" — or spend time in nature — for 10 minutes or more, at least three times a week over an eight-week period.
The participants could sit, walk or do both in an outdoor location of their choosing, on days of their choosing. Their "nature experience" was defined as "anywhere outside that, in the opinion of the participant, included a sufficiency of natural elements to feel like a nature interaction," according to the study. During that time (which was required to happen during daylight), they were not allowed aerobic exercise, social media, internet, phone calls, conversations or reading. Researchers measured levels of the stress hormone cortisol before and after their "nature pill" once every two weeks.
Researchers found that just a 20-minute immersion in nature was enough to significantly reduce cortisol levels in participants. More time — such as 20 to 30 minutes — spent in nature resulted in cortisol levels dropping at their greatest rate. Any longer than that and additional de-stressing benefits continued but at a slower rate.
"Healthcare practitioners can use our results as an evidence-based rule of thumb on what to put in a 'nature-pill' prescription," says Dr. Mary Carol Hunter, an associate professor at the University of Michigan and lead author of the research. "It provides the first estimates of how nature experiences impact stress levels in the context of normal daily life."
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