Shinrin-Yoku: A Boost for Your Immune System

As I walk through the forest, the dappled light illuminates the path ahead of me. A light mist swirls through the topmost layer of branches. I breathe in the gently scented air as pine leaves create a soft landing for each of my steps. I’ve come to the forest as a way to remember my breath, to reconnect with the truth in me.

As our days are filled with more and more technology—a constant state of “connection” with every bit of news, meals our friends are eating, and status updates—our stress response has been thrown out of balance. Our compulsion to check our phones and stay in the loop is taxing our nervous system and our immune system.

One way to counteract all this “techno-stress” is to spend time in forests. Dr Qing Li, an expert in forest medicine and Medical doctor at Tokyo’s Nippon Medical School, has published his research on how Shinrin-yoku, or forest bathing can bring healing to anyone who practices it. His book, Forest Bathing: How Trees Can Help you Find Health and Happiness he outlines the history of the practice as well as the many benefits if offers.

Li explains that shinrin-yoku can:

• Reduce blood pressure
• Lower stress
• Lift depression
• Improve energy
• Improve pain thresholds
• Boosts the immune system

One fascinating aspect of shinrin-yoku is how it works on the immune system. In his research, Li looked at how the activity of our natural killer (NK) cells are affected by practicing forest bathing. He writes, “natural killer cells are a type of white blood cell and are so called because they can attack and kill unwanted cells, for example, those infected with a virus, or tumour cells.” He found that both the number of NK cells and their activity increased significantly both immediately after practicing forest bathing, and up to thirty days later.

Li became curious about why our immune system was affected in this way. He knew that the five senses were involved in the effects, and he posited that our sense of smell as our “most primal” sense could be the reason. Trees emit a substance called phytoncides that are responsible both for protecting them from bacteria, insects and fungi, and also are “part of the communication pathway between trees: the way trees talk to each other.” Forest air, in addition to having high amounts of oxygen, are also full of phytoncides. Li found that exposure to phytoncides resulted in increased activity and number of NK cells as well as decreased stress hormones.

Another substance we are inhale in the forest is a “common and harmless bacteria, Mycobaterium vaccae.” This bacteria has been found through multiple studies to increase energy levels and lift mood. Through these connected pathways it also boosts the immune system.

The benefits of spending time in a forest are many varied. Li insists that if you live in a city, you can practice by visiting a park, or even a tree-lined street. In addition, diffusing essential oils that include forests scents and having indoor plants will all offer some benefit. The next time you feel yourself headed toward burn-out, plug yourself into a forest instead of your phone.