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Walking in the forest, one can't help but notice the smell of the pine trees, the sunlight falling on the rocks, the soft moss and ferns on the forest floor, and the sound of birds singing in the branches above. How does the simple act of walking through a forest impact one's body and mind?
The Japanese tradition of shinrin-yoku or “forest bathing" has inspired the modern concept of "forest therapy," or walking in the forest as a way to improve health and mood. Several studies over the past decade have found that being in a forest can lead to a relaxed and healthy well-being-- both physically and mentally-- and can even reduce blood levels of the stress hormone cortisol and boost the immune system.
Recent research published in the International Journal of Environmental Research and Public Health suggests that walking as little as 15 minutes in a forest can improve one's mood and relieve stress and anxiety. The study had 60 participants who were divided into two groups -- one that walked in a city environment and the other in a forest environment. People who walked for as little as 15 minutes in the forest experienced significantly less negative feelings and felt more relaxed both mentally and physically.
These findings are part of a growing body of evidence, including studies with larger participant numbers, that suggests forest therapy is a healthy and evidence-based way to reduce stress and anxiety.
Here are five findings from the research on forest therapy over the past decade:
1. Walking through the forest for can reduce anxiety and negative feelings such as anger and fatigue.
The recent study measured anxiety with the State–Trait Anxiety Inventory (STAI) and found that anxiety was significantly less for those that walked in the forest compared to those in the city. Furthermore, people who walked in the forest experienced significantly less negative feelings such as tension, anxiety, depression, anger, fatigue, and confusion.
2. Forest walking promotes relaxation.
Researchers examined heart rate, heart rate variability, and blood pressure and found that forest therapy activates the "relaxation response" branch of the nervous system, or parasympathetic nervous system.
3. Forest therapy may have antidepressant effects.
Small studies have found that forest therapy can improve mood and reduce depressive symptoms, including a study in children. Forest walking can be especially useful since it combines mindfulness in nature with exercise-- both of which are known to reduce depressive symptoms.
4. A brief walk in the forest for 15 minutes can result in a better state of mind.
You do not have to walk for long periods in the forest order to reap the mental or physical benefits of forest therapy. Research has found that as little as 15 minutes of walking in the forest can make a big difference in putting your body and mind at ease.
5. Walking in nature may improve your immune system with lasting benefits.
Studies have found that walking in a forest could increase "natural killer" cell activity and boost immunity-- and these protective benefits can last over a month.
6. "Forest bathing" may boost healthy antioxidants.
A small number of studies have measured antioxidant levels in the blood after forest bathing and found that helpful antioxidants increased significantly.
Science continues to suggest that forest therapy has healing and immune-boosting powers, including anti-anxiety and antidepressant effects.
Copyright © 2021 Marlynn Wei, MD, PLLC
