The idea of retreating to nature when life gets too hectic is nothing new. For instance, this study suggests that negative ions in natural environments benefit those suffering from depression and anxiety and contribute to feelings of mental-wellbeing. But, for the first time ever researchers have deduced a specific dose of an urban nature experience to counteract the effects of stress. The researchers concluded that a 20-minute “nature pill” is sufficient to significantly reduce stress hormone levels.
“We know that spending time in nature reduces stress, but until now it was unclear how much is enough, how often to do it, or even what kind of nature experience will benefit us,” says Dr. MaryCarol Hunter, an Associate Professor at the University of Michigan and lead author of the research. “Our study shows that for the greatest payoff, in terms of efficiently lowering levels of the stress hormone cortisol, you should spend 20 to 30 minutes sitting or walking in a place that provides you with a sense of nature.”
The study was published in Frontiers in Psychology. The researchers hope the finding encourages health practitioners to consider prescribing a “nature pill” before conventional treatments.
As GoodNewsNetwork reports, nature pills could be a low-cost solution to reduce the health effects associated with high stress levels which stem from growing urbanization and indoor lifestyles. Hunter and her colleagues wanted to provide evidence-based guidelines for prescribing a nature pill, so they designed an experiment that gives a realistic estimate of an effective dose.
Over an 8-week period, participants of the study were asked to take a nature pill with a duration of 10 minutes or more, at least 3 times a week. Before and after the nature pill, levels of cortisol, a stress hormone, were measured from saliva samples.
“Participants were free to choose the time of day, duration, and the place of their nature experience, which was defined as anywhere outside that in the opinion of the participant, made them feel like they’ve interacted with nature,” explained Hunter. “There were a few constraints to minimize factors known to influence stress: take the nature pill in daylight, no aerobic exercise, and avoid the use of social media, internet, phone calls, conversations and reading.
Building personal flexibility into the experiment allowed us to identify the optimal duration of a nature pill, no matter when or where it is taken, and under the normal circumstances of modern life, with its unpredictability and hectic scheduling,” she continued. “We also accommodated day-to-day differences in a participant’s stress status by collecting four snapshots of cortisol change due to a nature pill,” says Hunter. “It also allowed us to identify and account for the impact of the ongoing, natural drop in cortisol level as the day goes on, making the estimate of effective duration more reliable.”
After analyzing the data, the researchers concluded that a 20-minute nature experience is enough to significantly reduce cortisol levels. They also found that if you spend more time in nature (between 20 and 30 minutes), cortisol levels dropped at the greatest rate. Past 30 minutes, additional de-stressing benefits continue to add up, albeit 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,” said Hunter. “It provides the first estimates of how nature experiences impact stress levels in the context of normal daily life. It breaks new ground by addressing some of the complexities of measuring an effective nature dose.”
Hunter and her colleagues hope that this study inspires further research in this area.
“Our experimental approach can be used as a tool to assess how age, gender, seasonality, physical ability and culture influences the effectiveness of nature experiences on well-being. This will allow customized nature pill prescriptions, as well as a deeper insight on how to design cities and wellbeing programs for the public,” Hunter concluded.