Vanderbilt’s campus is a designated arboretum — home to 6,181 trees as of 2013 — so students can take advantage of the Japanese tradition of shinrin-yoku (森林浴), or “forest bathing.” The practice of shinrin-yoku entails being mindful of one’s environment and being present with the help of trees. In the 1980s, shinrin-yoku arose as a form of preventative healthcare in response to the increased number of stress-related illnesses and tech-driven lifestyles. Since then, shinrin-yoku has been a key component of Japan’s public health.
The word shinrin-yoku is made of three characters, which offer a glimpse into its meaning. The first, 森 “shin,” means “forest” and is a collection of three branch-like 木 “ki” sub-characters that stand for “tree.” The second character, 林 “rin,” stands for “wood” or “grove” and is composed of two 木 characters. Finally, the last character of 浴 “yoku” stands for “bath/bathing,” as in an individual peacefully absorbing the energy of the forest for rejuvenation.
Some of the health benefits of shinrin-yoku include:
1. Reducing stress: Numerous studies have shown that time spent in forest environments can significantly reduce levels of cortisol, which is the body’s primary stress hormone. A 2010 study found that participants who partook in forest walks experienced lower blood pressure, reduced heart rates, and improved mood compared to those who walked in urban settings.
2. Boosting the immune system: An interesting aspect of shinrin-yoku is exposure to phytoncides, aromatic compounds released by evergreen trees with needle-like or scale-like leaves. These compounds have been shown to elevate the activity of natural killer cells, a form of white blood cell critical for combating infections and tumors. In one Japanese study, increased NK cell activity was maintained for up to a week after a two-to-three day forest trip.
3. Improving depression and anxiety: Forest bathing has been connected to reduced symptoms of depression and anxiety. Being in nature can lead the brain into a more relaxed state by encouraging activity of the parasympathetic nervous system, which is why nature seems to have a calming effect on people. MRI scans show that walking outdoors in nature results in less brain activity in areas linked to rumination, or repetitive thought associated with excessive worrying and depression.
4. Supporting cardiovascular health: Being surrounded by nature has also been linked to a decrease in blood pressure and improvements in heart rate variability for increased cardiovascular resiliency. A study in 2017 demonstrated that the practice of “forest bathing” can serve as a positive non-pharmacological intervention for heart health.
By going outside to enjoy the many trees on Vanderbilt’s campus or heading to a nature reserve such as Nashville’s Shelby Bottoms or Radnor Lake, students can reap the psychological and immunological benefits of shinrin-yoku. Beyond personal wellness, shinrin-yoku highlights a larger message: that our health is deeply connected to the health of our environment.
References
Hansen, M. M., Jones, R., & Tocchini, K. (2017). Shinrin-Yoku (forest bathing) and nature therapy: A state-of-the-art review. International Journal of Environmental Research and Public Health, 14(8), 851.
Li, Q., Morimoto, K., Nakadai, A., Inagaki, H., Katsumata, M., Hirata, Y., … & Miyazaki, Y. (2008). Forest bathing enhances human natural killer activity and expression of anti-cancer proteins. Environmental Health and Preventive Medicine, 13(2), 55–63.
Park, B. J., Tsunetsugu, Y., Kasetani, T., Kagawa, T., & Miyazaki, Y. (2010). The physiological effects of Shinrin-yoku (taking in the forest atmosphere): Evidence from field experiments in 24 forests across Japan. Environmental Health and Preventive Medicine, 15(1), 18–26.
Song, C., Ikei, H., & Miyazaki, Y. (2017). Blood pressure-lowering effect of Shinrin-yoku: A systematic review and meta-analysis. BMC Complementary and Alternative Medicine, 17, 409. Nature Therapy Association+2
Vanderbilt University. (n.d.). Facts about the Arboretum. Vanderbilt University. https://www.vanderbilt.edu/trees/about/