Advaya: Qing, your book Into The Forest examines the unprecedented benefits of the world’s largest natural health resource: the great outdoors. In what ways are nature and improved wellbeing linked?
QING: Forests (and nature in general) stimulate the five senses to produce benefits and improve wellbeing:
Sense of sight: Green colour, yellow colour, natural colours, forest and natural landscape Sense of smell: Special good smell, fragrance from plants and trees called phytoncides Sense of hearing: Forest sounds, nature sounds, bird song, murmuring of river, sounds of the wind, etc Sense of touch: Touching trees, putting your whole body in the forest and nature atmosphere. Sense of taste: Eating foods from forests and nature, tasting the fresh air in forests and nature, drinking water from forest and nature.
This is a total effect of five senses. The quiet atmosphere, beautiful scenery, mild climate, special good smell, and fresh, clean air in forests and in nature all contribute to improved wellbeing.
Advaya: How did your journey of research into forest bathing begin? How did your life lead you to becoming a Forest Medicine expert?
QING: It is a long story. I’ve loved nature and forests since my childhood - I was born in a small village in China, where there were green poplar forests and a beautiful apricot forests in my village, which flowered pink all through April.
In 1988, I came to Japan to study at Kagoshima University. At that time, I visited a very beautiful forest with my friends in Yakushima, a small island covered with this mysterious, glowing, green - from the end of April to the beginning of May of 1988. The quiet atmosphere, beautiful scenery, mild climate, special good smell, and fresh, clean air in the forest, as well as big Japanese cedar trees, (including Jomon Sugi which is over 7000 years old), made me very content and relaxed. Thankful for all this bounty and beauty, I became convinced that forest-bathing was absolutely essential to human health. That fascinating, inspiring visit was to have an important impact on the whole direction of my life and my future research.
I majored in environmental medicine and got my PhD degree from Kagoshima University in 1992 before moving to Tokyo. After that, I began studying the effects of environmental chemicals, stress and lifestyle on immune function and human health at both Kagoshima University and Nippon Medical School. I also began looking at the effects of forests on human health. From 2001 to 2002, I studied at Stanford University, on the topic of anticancer protein, granulysin in human natural killer cells (immune cells).
Because of my background, I was invited to be a key member of the research team put together by the Forest Agency of Japan in 2004, to study forest bathing.
I have always wanted to know why we feel so much better when we are in forests. What is this secret power of trees that makes us so much healthier and happier? Why is it that we feel less stressed and have more energy just by walking in the forest? I study forest medicine to find out all the ways in which walking in the forest can improve our well-being.
I had the following hypothesis before Forest Bathing study: It is well known that immune system including natural killer (NK) cells play an important role in defence against bacteria, viruses and tumors. It is also well known that stress inhibits immune function. As a common sense, forest bathing/shinrin-yoku may reduce stress. Thus, I speculated that forest bathing/shinrin-yoku may have beneficial effect on immune function by reducing stress.
Since 2004 I have conducted many studies to investigate the effect of forest environments (shinrin-yoku) on human health. Eventually, my research team and I established a new science called Forest Medicine, and published a book with the same name. (2012)
My newer book, Shinrin-Yoku (The Art and Science of Forest Bathing – How Trees Can Help You Find Health and Happiness) was published by Penguin Random House UK in 2018 and was a bestseller in the USA. The book has been translated into over 26 languages.
Recently, I co-edited International Handbook of Forest Therapy published in 2019 by Cambridge Scholars Publishing.
Advaya: What are the health benefits you’ve studied?
QING: I have found that Shinrin-Yoku (forest bathing):
- Boosts immune function by increasing natural killer activity and anticancer proteins such as perforin, granulysin and granzymes.
- Reduces stress hormones such as adrenaline, noradrenaline and cortisol.
- Reduces the activity of sympathetic nerve and increases the activity of parasympathetic nerve and shows a relaxing effect.
- Improves sleep.
- Has a preventive effect on depression.
- Reduces blood pressure and heart rate and shows a preventive effect on hypertension and heart disease.
- May apply to rehabilitation medicine.
- In city parks, also has benefits on human health.
- Has a preventive effect on lifestyle related diseases by reducing stress. Stress can induce many conditions such as cancers, hypertension, depression, cardiovascular diseases (myocardial infarction), stroke (cerebral haemorrhage), gastric ulcers, obesity, alcoholism, panic disorder, eating disorder.
You name it.
Shows a preventative effect on COVID-19 by reducing metal stress and by boosting immune function.
Advaya: Beyond the personal benefits of forest bathing, do you see this kind of practice as powerful in helping to transform our social and ecological crises?
QING: Yes. If people know the health benefits of forests, they will protect the forests. Therefore, forest bathing is a powerful practice for helping to transform our social and ecological crises.
Advaya: Do you see forest bathing as a spiritual practice?
QING: In Japan, forest bathing is also a spiritual practice. Both of Japan’s official religions – Shinto and Buddhism – believe that the forest is the realm of the divine. In Shinto, the spirits are not separate from nature, they are in it. They are in the trees, in the rocks, in the breeze, the stream, the waterfall. These spirits are called Kami. There are millions and millions of Kami. They can be everywhere in nature. And the places where gods live can become the places of worship themselves. It is not unusual in Japan to find people worshipping in the forest.
Advaya: What is it about forests (as opposed to other environments) that make them so beneficial to human health?
QING: It is the total effect of the five senses. The sense of smell actually has the biggest effect - owing to the phytoncides or essential oils coming from trees. My research has found that these boost immune function and reduce stress hormones. You can read more about this in the following articles:
Phytoncides (wood essential oils) induce human natural killer cell activity. Li Q, Nakadai A, Matsushima H, Miyazaki Y, Krensky AM, Kawada T, Morimoto K.Immunopharmacol Immunotoxicol. 2006;28(2):319-33. doi: 10.1080/08923970600809439.PMID: 16873099
Effect of phytoncide from trees on human natural killer cell function. Li Q, Kobayashi M, Wakayama Y, Inagaki H, Katsumata M, Hirata Y, Hirata K, Shimizu T, Kawada T, Park BJ, Ohira T, Kagawa T, Miyazaki Y.Int J Immunopathol Pharmacol. 2009 Oct-Dec;22(4):951-9. doi: 10.1177/039463200902200410.PMID: 20074458
Advaya: How would you like to see humanity shift its behaviours and narratives in order to protect and care for our forests more?
QING: The key to preserving our forest, wherever it is, is to maintain our connection with it, and one of the best ways to do that is to remind people that our health and the health of our communities depends on it. When we feel connected to nature, we want to look after it. And this in turn is good for our health. We benefit not just from the clean air and water forests provide, the carbon they store, the species they maintain, but also from the peace and quiet they offer, their beauty and vital spirit, and the myriad benefits to our well-being they hold within them.
As more and more of us have moved into the city, fewer and fewer of our children have the same access to nature that we had, or that their grandparents had. In Last Child in the Woods, Richard Louv came up with the term ‘nature deficit disorder’, linking the lack of nature in young people’s lives to the rise in behavioural disorders, depression and obesity, in addition to the lack of vitamin D and the increase in shortsightedness that we see when children don’t spend enough time outdoors.
As the American Medical Association put it as long ago as 2005, ‘Children will be smarter, better able to get along with each other, healthier and happier when they have regular opportunities for free and unstructured play in the out-of-doors.’ Most importantly, if children play out of-doors, they will grow up with a connection to nature and thus the wish to protect it. All the research shows that we will look after what we love. If we give our children these experiences, they will love the places in the forest where they played and learnt. If we let our young people engage with the beauty of the natural world they will learn to love and understand its spirit. In the end, it is our children’s relationship with the natural world that will determine its future. If we let our children go into the forest, they will become adults who will protect it.
Advaya: When/where did forest bathing originate?
QING: Shinrin-yoku was proposed in 1982 in Japan, by researchers trying to find methods for reducing stress. Akasawa Natural Recreation Forest in Nagano prefecture has been designated as the birthplace of forest bathing in Japan.
Shinrin in Japanese means ‘forest’, and yoku means ‘bath’. So shinrin-yoku means bathing in the forest atmosphere, or taking in the forest through our senses. This is not exercise, or hiking, or jogging. It is simply being in nature, connecting with it through our sense of sight, hearing, taste, smell and touch.
Shinrin-yoku is like a bridge. By opening our senses, it bridges the gap between us and the natural world.
Advaya: How important is forest bathing in the context of Covid-19?
QING: Immune function is crucial in preventing Covid-19. Elderly people with impaired immune function, as well as patients with underlying diseases the reduce their immune function, such as diabetes, hypertension, heart diseases and respiratory diseases, are more susceptible to Covid-19. Because forest bathing boosts immune function, it may have a preventative effect on Covid-19.
Forest bathing also reduces the symptoms of anxiety, depression, anger, fatigue and confusion related to lockdown and isolation. Therefore it may have a preventative effect on Covid-19 induced stress disorders.
