A research done by the University of Illinois and the University of Hong Kong has determined something that’s hopefully not a surprise to many people – having more trees around us can help reduce stress (1).
The researchers showed several 6-minute long 3D clips to 160 participants after first subjecting them to various stressful situations – delivering speeches, performing tests, etc. The video clips showed cities with varying densities of tree covers. Some had no trees whatsoever, others included up to 70% trees. The end result of the test was that the more trees each video included, the faster and more comprehensively the participants calmed down after their stressful exposure.
This isn’t the only study that showed these kind of results. A previous study from 2016 was published in the International Journal of Environmental Research and Public Health and looked at physiological markers of stress in their participants instead of asking them for their feedback (2). Nevertheless, the results were quite similar (3):
“The findings suggest that keeping a few snapshots of greenery around your work desk might not be a bad idea. When participants viewed the natural images in the experiment, their stress levels lowered, thanks to the activation of their parasympathetic nervous system – which controls certain rest functions,” according to Science Alert.
The parasympathetic system is responsible for slowing down our heart rates, stimulating our salivary glands, and increasing heart-rate variability. On the other end, our sympathetic nervous system controls our fight-or-flight impulses such as myocardial contractility, increased heart rate, sweat production, and others.
“High levels of parasympathetic activity have been associated with numerous benefits including more adaptive emotion regulation strategies and decreased risk of cardiovascular disease,” the researchers added.
In conclusion, not only should we have more walks and hikes in nature at least once per week, but we should also make sure to surround ourselves with as much greenery as possible in our daily lives, whether it’s just indoor green flowers or trees outside our windows.