Human beings have always appreciated the forest for the peaceful atmosphere that reigns there, the harmony of the landscapes, the mild climate, the pleasant scents, and the fresh and pure air.
What if our walks in the woods gave us much more than this delicious feeling of zenitude?
In Japanese, shinrin means "forest" and yoku means "bath". Thus, shinrin-yoku, or “forest bath”, means to bathe in the atmosphere of the forest, or to soak up the forest through our senses.
Recognized in Japan since 1982, forest bath therapy was widely popularized by Dr Qing Li, an immunologist in the Department of Public Health at the University of Tokyo.
To date, accompanied forest bathing is reimbursed by health insurance in Japan, China and Korea, and Japanese universities offer a medical specialization in "silvotherapy".
Not surprisingly, the concept of forest bathing is gaining traction across the globe in response to the hectic daily life of our modern society.
Several studies have shown that immersion in a forest environment, after only 40 minutes, has the power to reduce mental stress and anxiety, anger, fatigue and confusion, and to increase attention and attention skills. concentration. Decreased stress hormone cortisol, heart rate and blood pressure have been observed, as well as decreased activity in the prefrontal area of the brain.
Dr. Qing Li, for his part, was interested in the action of forest baths on the immune system. Among other things, he studied subjects who had spent three days and two nights in the forest. Conclusion? This immersion strongly stimulated the immune cells NK (Natural killer), involved in the prevention of certain infections and preventing the development of tumor cells.
Surprisingly, the increase in NK cell activity continued for more than a month after the three days in the forest. In contrast, a three-day sightseeing visit to a city has no effect on increasing the number or activity of NK cells.
Molecules called phytoncides, emitted by trees to defend themselves against pathogenic bacteria and fungi, are the basis of the beneficial effects of forest bathing.
Several of these molecules, which we can inhale in certain forests, in particular coniferous trees, are found in the terpene family: limonene, pinene ... Phytoncides have a beneficial action on the parasympathetic nervous system, which among other things regulates all the functions relaxation of the body. The silence and the sounds of nature also stimulate parasympathetic function.
Colours of freedom, balance and relaxation, the multiple shades of blue and green seen as the sun shines through the leaves of trees reassure the brain, causing it to slow down.
The light spectrum of natural light also optimally covers all human physiological needs (hormonal secretion, cognition, sleep, mood, etc.), unlike artificial lights.
The leaves of trees act as natural filters capable of purifying the air. The polluting particles are admirably retained by the micro-hairs, invisible to the naked eye, present on all the leaves. Thus, the air in the forest is between a hundred and a thousand times cleaner depending on the region, compared to the city. The brain works better.
Negative ions, abundant in forest environments and capable of neutralizing free radicals, are also said to have an energizing and refreshing effect contributing to greater clarity of mind and a feeling of overall well-being.
In almost all forest soils, we find this bacterium, a priori banal. Yet recent studies have shown it to act as a "natural antidepressant" by stimulating the brain's release of serotonin and dopamine. Beneficial effects on the immune system and on cognitive capacities have also been observed on contact (touch, inhalation of ambient microparticles, etc.)
During a forest bath, you obviously abandon your concerns, but also your cell phone and camera! Bring a small blanket to sit on, water to drink and a little snack if needed.
The idea is to awaken the five senses to everything that surrounds us, as we take the opportunity to look at the moss on the rocks, listen to the birdsong, the murmur of the stream, touch the trees, breathe deeply, taste a wild blackberry picked on the way ...
This is not a workout. We move very slowly, and we land according to our desires, to contemplate, quite simply ...
From the very first session, the forest bath leads us to refocusing, reconnecting with the essential, feeling amazed by the beauty of living things.
So, shall we try?
Li, Quing. (2018). Shinrin yoku : l'art et la Science du bain de forêt. Paris: Éditions First, 309 p.
Kotera, Y., Richardson, M. & Sheffield, D (2020). Effects of Shinrin-Yoku (Forest Bathing) and Nature Therapy on Mental Health: A Systematic Review and Meta-Analysis. Int. J. Ment. Health Addict; 1-25.
Antonelli, M., Barbieri, G. & Donelli, D. (2019). Effects of forest bathing (shinrin-yoku) on levels of cortisol as a stress biomarker: A systematic review and meta-analysis. Int. J. Biometeorol; 63, 1117–1134.
Ideno, Y., Hayashi, K., Abe, Y. & al. (2017). Blood pressure-lowering effect of Shinrin-yoku (Forest bathing): A systematic review and meta-analysis. BMC Complement. Altern. Med; 17: 409.
Putra, R.R.F.A., Veridianti, D.D., Nathalia, E. & al. (2018). Immunostimulant effect from phytoncide of forest bathing to prevent the development of cancer. Adv. Sci. Lett; 24, 6653–6659.
Li, Q. (2010). Effect of forest bathing trips on human immune function. Environ. Health Prev. Med; 15(1): 9–17.