Many of us feel a sense of peace in a forest. I have no doubt that this is the result of several factors including sounds and frequencies (e.g., infrasound), increased negative charge, scents, wood essential oils, genetic heritage and memory, and simple aesthetic appreciation and beauty.

Even five minutes around trees may improve health.

The New York State Department of Environmental Conservation recently posted an article on its website entitled: “Immerse Yourself in a Forest for Better Health.” Immerse is a most appropriate word here. As with water, that is what you are doing when you enter a forest and breathe in the water vapour, rich in aerosols, that trees are releasing through evapotranspiration: you are “forest bathing.”

Scientific studies around the world are exploring the health benefits of spending time outside in natural environments, green spaces, and forests. Studies have also shown that different trees provide different benefits. A recent study by Lancaster University showed the birch tree’s detoxifying capabilities when they planted silver birch trees between a street of houses and a busy road. According to Professor Barbara Maher, the trees absorbed more than 50 per cent of the particulate dust — linked to respiratory problems — from passing traffic, much more than other species, such as oak.

The tree “is a chemical factory,” says botanist and biochemist Diana Beresford-Kroeger. They broadcast a host of chemicals into the environment that may travel for hundreds of kilometres, as well as affect the immediate area.

Beresford-Kroeger believes that trees help maintain the health of the natural world, as they constantly shower healing chemical mists into the air. “These substances are at the heart of connectivity in nature,” says Beresford-Kroeger. for instance, during a walk through a pine forest on a warm day, the sharp pungent smell of pinene (a monoterpene), helps to relieve asthma. Another monoterpene aerosol, limonene, has an ability to fight cancer, demonstrated by Dr. Michael Gould at the University of Wisconsin.

Scientific studies have proven (see reference list) that forests:

• Boost our immune system
• Lower our blood pressure
• Reduce stress
• Improve our mood
• Increases our ability to focus (even in children with ADHD)
• Accelerate recovery from surgery or illness
• Increase our energy levels
• Improve our sleep

Immune System

When we walk and breathe in a forest, we are breathing in multiple aerosols given off by trees. Among these airborne chemicals are phytoncides that plants give off to protect themselves from insects. The antifungal and antibacterial qualities of phytoncides fight disease. When we breathe in phytoncides, our bodies increase the. Activity of our white blood cells; the same ones that kill tumor- and virus-infected cells.

Stress & Cognition

Studies have shown that just spending time in a forest reduces blood pressure and stress-related hormones cortisol and adrenalin. Researchers discovered that forest bathing significantly decreased scores for anxiety, depression, anger, confusion, and fatigue.

Researchers in Europe and Japan found that the amount of green space and proximity to a person’s home reliably predicted mental and physical health. Anxiety and depression was significantly reduced in the presence of green space. Vegetation creates “a halo of improved health.” Dr. Frances Kuo at the University of Illinois demonstrated that just seeing a tree helps cognition and promotes a sense of well-being. Kuo strongly believes that lack of trees is debilitating to general social health. “A disappearing urban forest leads to psychological, physical, and social breakdown,” says Kuo, “Just as animals in unfit environments develop certain behavioural and functional pathologies, we may see more child abuse or crime or their problems when people live in unfit environments.”

Focus & ADHD

Spending time in Nature, looking at plants, water, birds, and other natural phenomena, gives the cognitive portion of our brain a break from what some call “Directed Attention Fatigue”, allowing us to focus better and renew our ability to be patient. A study published in 2000 by environmental psychologist Nancy Wells found that ample daylight and greenery boosted attentiveness, focus and academic performance. A UK study demonstrated that a spacious and attractive courtyard encourages positive social interaction. In her August 2015 presentation at the ISA Annual Conference in Orlando, Florida, Ellen Vincent reported on therapeutic benefits of Nature images in various settings. Studies conducted from the 1980s to the present have indicated that Nature views reduce stress, anxiety and pain and that architecture affects medical outcomes.

The New York State article added that, “The part of the brain affected by attention fatigue (right prefrontal cortex) is also involved in Attention-Deficit/Hyperactivity Disorder (ADHD). Studies show that children who spend time in natural outdoor environments have a reduction in attention fatigue and children diagnosed with ADHD show a reduction in related symptoms. Researchers are investigating the use of natural outdoor environments to supplement current approaches to managing ADHD. Such an approach has the advantages of being widely accessible, inexpensive and free of side effects.”

Surgery

“Hospital patients may be stressed from a variety of factors, including pain, fear, and disruption of normal routine,” says the article. “Research found that patients with “green” views had shorter postoperative stays, took fewer painkillers, and had slightly fewer postsurgical complications compared to those who had no view or a view of a cement wall.”

In 1982, the Japanese Ministry of Agriculture, Forestry and Fisheries recognized the beneficial qualities of forests in health and promoted the practice of Shinrin-yoku, which means taking in the forest atmosphere or “forest bathing”. Shinrin-yoku  (or “wood-air bathing”) is now a recognized practice in the east and is gaining interest in the West (particularly in Ontario and British Columbia) as a natural form of aromatherapy and relaxation therapy.

 

References:

Akers, A., Barton, J., Cossey, R., Gainsford, P., Griffin, M., Mikleright, D. 2012. “Visual Color Perception in Green Exercise: Positive Effects on Mood and Perceived Exertion”.  Environmental Science and Technology. 46(16):8661-8666. http://www.ncbi.nlm.nih.gov/pubmed/22857379.

Aspinall, P., Mavros, P., Coyne, R., Roe, J. 2012. “The urban brain: analyzing outdoor physical activity with mobile EEG”.  British Journal of Sports Medicine. http://www.ncbi.nlm.nih.gov/pubmed/23467965.

Barton, J., Pretty, J. 2010. “What is the Best Dose of Nature and Green Exercise for Improving Mental Health? A Multi-Study Analysis”. Environmental Science and Technology. 44: 3947-3955. http://www.ncbi.nlm.nih.gov./pubmed/20337470.

Beresford–Kroeger, Diana. 2003. “Arboretum America: A Philosophy 
of the Forest.” University of Michigan Regional. 214 pp.

Berman, M. G., Jonides, J., Kaplan, Stephen. 2008. “The Cognitive Benefits of Interacting With Nature”. Psychological Science. 19: 1207-1212. http://libra.msra.cn/Publication/6994981/the-cognitive-benefits-of-interacting-with-nature.

Children and Nature Network. 2012. “Health Benefits to Children from contact with the Outdoor & Nature”. 46 pages. http://www.childrenandnature.org/downloads/CNNHealthBenefits2012.pdf. http://www.childrenandnature.org/.

Donovan, G. Butry, D. Michael, Y., Prestemon, J., Liebhold,A., Gatziolis, D., Mao, M. 2013. “The Relationship Between Trees and Human Health: Evidence from the Spread of the EAB”.  American Journal of Preventive Medicine. 44(2):139-45.  http://californiareleaf.org/trees-in-the-news/the-relationship-between-trees-human-health.

Gies, E. 2006. “The Health Benefits of Parks”. The Trust for Public Land. http://www.tpl.org/publications/books-reports/park-benefits/the-health-benefits-of-parks.html.

Hanson, P., Matt, F., Bowyer, J.,Bratkovich, S., Fernholz, K., owe, J., Groot, H., Pepke, E. 2016. “The Human Health and Social Benefits of Urban Forests”. Dovetail Partners Inc. (1 MB PDF, 12 pages)

Kaplan, R., Kaplan, S. 1989. “The experience of nature: A psychological perspective”. New York: Cambridge University Press.

Kuo, F. E., Taylor, A. F. 2004. “A Potential Natural Treatment for Attention-Deficit /Hyperactivity Disorder: Evidence From a National Study”.  American Journal of Public Health. 94(9): 1580-1586. http://www.ncbi.nlm.nih.gov/pmc/articles/pmc1448497/.

Lee, J., Park, B.-J., Tsunetsugu, Y., Kagawa, T., Miyazaki, Y. 2009. “Restorative effects of viewing real forest landscapes, based on a comparison with urban landscapes”. Scandinavian Journal of Forest Research. 24(3): 227-234. http://www.tandfonline.com/doi/abs/10.1080/02827580902903341#preview.

Lee, J., Park, B.-J., Tsunetsugu, Y., Ohra, T., Kagawa, T., Miyazaki, Y. 2011. “Effect of forest bathing on physiological and psychological responses in young Japanese male subjects”. Public Health. 125(2): 93-100. http://www.sciencedirect.com/science/article/pii/S0033350610003203.

Li, Q. 2010. “Effect of forest bathing trips on human immune function”. Environmental Health and Preventative Medicine. 15(1): 9-17. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2793341/.

Li, Q., Kawada, T. undated. “Healthy forest parks make healthy people: Forest environments enhance human immune function”. Department of Hygiene and Public Health, Nippon Medical School, Tokyo, Japan. http://www.hphpcentral.com/wp-content/uploads/2010/09/5000-paper-by-Qing-Li2-2.pdf.

Li, Q., Kobayashi, M., Kawada, T. 2008. “Relationships Between Percentage of Forest Coverage and Standardized Mortality Ratios (SMR) of Cancers in all Prefectures in Japan”. The Open Public Health Journal. 1: 1-7. http://www.benthamscience.com/open/tophj/articles/V001/1TOPHJ.pdf.

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. 2009. “Effect of phytoncide from trees on human natural killer cell function”.  International Journal of Immunopathology and Pharmacology. 22(4):951-959. http://europepmc.org/abstract/MED/20074458/reload=0;jsessionid=BnlPLmTxArJ6VpF0s4MU.6.

Li, Q., Morimoto, K., Nakadai, A., Inagaki, H., Katsumata, M., Shimizu, T., Hirata, Y., Hirata, K., Suzuki, H., Miyazaki, Y., Kagawa, T., Koyama, Y., Ohira, T., Takayama, N., Krensky, A.M., Kawada, T. 2007.  “Forest bathing enhances human natural killer activity and expression of anti-cancer proteins”. International Journal of Immunopathology and Pharmacology. 20(2 Suppl 2):3-8.
http://www.ncbi.nlm.nih.gov/pubmed/17903349.

Li, Q., Nakadai, A., Matsushima, H., Miyazaki, Y., Krensky, A., Kawada, T., Morimoto, K. 2006. “Phytoncides (Wood Essential Oils) Induce Human Natural Killer Cell Activity”. Immunopharmacology and Immunotoxicology, 28:319-333. http://www.ncbi.nlm.nih.gov/pubmed/16873099.

Maas, J., Verheij, R., Groenewegen, P., de Vries, S., Spreeuwenberg, P. 2006. “Greenspace, urbanity, and health: how strong is the relation?” Journal of Epidemiology and Community Health. 60(7): 587-592. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2566234/.

Maller, C., Henderson-Wilson, C., Pryor, A., Prosser, L., Moore, M. 2008. “Healthy parks, healthy people: The health benefits of contact with nature in a park context. A review of relevant literature”. 2nd edition. Parks Victoria.  http://parkweb.vic.gov.au/about-us/healthy-parks-healthy-people/the-research.

Mao G.X., Cao, Y.B., Lan, X.G., He, Z.H., Chen, Z.M., Wang, Y.Z., Hu, X.L., Lv, Y.D., Wang, G.F., Yan, J. 2012. “Therapeutic effect of forest bathing on human hypertension in the elderly”. Journal of Cardiology. 60:495-502.  http://www.sciencedirect.com/science/article/pii/S0914508712001852.

Munteanu, Nina. 2016. “Water Is… The Meaning of Water.” Pixl Press, Vancouver, B.C. 583pp.

Munteanu, Nina. 2016. “Why I Love Trees: Part 1, Drinking Trees.” The Meaning of Water, June 9, 2016. https://themeaningofwater.com/2016/06/09/why-i-love-trees-part-1-drinking-trees/

Munteanu, Nina. 2016. “Why I Love Trees: Part 2, Breathing Trees.” The Meaning of Water, June 11, 2016. https://themeaningofwater.com/2016/06/11/why-i-love-trees-part-2-breathing-trees/

Munteanu, Nina. 2016. “Why I Love Trees: Part 3, Feeling Trees.” The Meaning of Water, June 13, 2016. https://themeaningofwater.com/2016/06/13/why-i-love-trees-part-3-feeling-trees/

New York State, Department of Environmental Conservation. “Immerse Yourself in a Forest for Better Health.” http://www.dec.ny.gov/lands/90720.html

Ohtsuka, Y., Yabunaka, N., Takayama, S. 1998. “Shinrin-yoku (forest-air bathing and walking) effectively decreases blood glucose levels in diabetic patients”. International Journal of Biometeorology. 41(3):125-7. http://www.ncbi.nlm.nih.gov/pubmed/9531856.

Park, B.-J., Furuya, K., Kasetani, T., Takayama, N., Kagawa, T., Miyazaki, Y. 2011. “Relationship between psychological responses and physical environments in forest settings”. Landscape and Urban Planning. 102(1): 24-32. http://www.sciencedirect.com/science/article/pii/S0169204611001368.

Park, B.-J., Tsunetsugu, Y., Kasetani, T., Kagawa, T., Miyazaki, Y. 2010. “The physiological effects of Shinrin-yoku (taking in the forest atmosphere or forest bathing): evidence from field experiments in 24 forests across Japan”. Environmental Health and Preventative Medicine. 15(1):18-26. http://www.ncbi.nlm.nih.gov/pubmed/19568835.

Taylor, A. F., Kuo, F. E. 2009. “Children with attention deficits concentrate better after a walk in the park”.  Journal of Attention Disorders. 12(5): 402-409. http://jad.sagepub.com/content/12/5/402.

Thompson, C. W., Roe, J., Aspinall, P., Mitchell, R., Clow, A., Miller, D. 2012. “More green space is linked to less stress in deprived communities: Evidence from salivary cortisol patterns”. Landscape and Urban Planning. 105(3): 221-229. http://www.sciencedirect.com/science/article/pii/S0169204611003665.

Townsend, M. 2008. “Healthy parks, healthy people: The health benefits of contact with nature in a park context. A review of relevant literature”. Deakin University.Burwood, Melbourne, Australia. http://parkweb.vic.gov.au/__data/assets/pdf_file/0018/313821/HPHP-deakin-literature-review.pdf.

Tsunetsugu, Y., Lee, L., Park, B.-J., Tyrväinen, L., Kagawa,T., Miyazaki, Y. 2013. “Physiological and psychological effects of viewing urban forest landscapes assessed by multiple measurements”.  Landscape and Urban Planning. 113: 90-93. http://www.sciencedirect.com/science/article/pii/S0169204613000212.

Tsunetsugu, Y., Park, B., Miyazaki, Y. 2010. “Trends in research related to “Shinrin-yoku” (taking in the forest atmosphere or forest bathing) in Japan”. Environmental Health and Preventative Medicine. 15(1): 27-37.  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2793347/.

Ulrich, R. S. 1984. “View through a window may influence recovery from surgery”. Science. 224:420-422.

Ulrich, R. S. 1999. “Effects of gardens on health outcomes: Theory and research”. In C. Cooper-Marcus & M. Barnes (Eds.), Healing Gardens: Therapeutic Benefits and Design Recommendations. New York: John Wiley, pp. 27-86. http://www.majorfoundation.org/pdfs/Effects%20of%20Gardens%20on%20Health%20Outcomes.pdf.

Society for Forest Medicine within the Japanese Society for Hygiene, http://forest-medicine.com/page11.html.

University of Washington. Urban Forestry and Human Benefits. http://www.naturewithin.info/urban.html.

University of Illinois at Urbana-Champaign, Landscape and Human Health Laboratory, http://lhhl.illinois.edu/adhd.htm.

Wells, Nancy M. 2000. “At Home with Nature: Effects of ‘Greenness’ on Children’s Cognitive Functioning”. Environment and Behavior 32 (6): 775–795.

 

Nina Munteanu is an ecologist, limnologist and internationally published author of award-nominated speculative novels, short stories and non-fiction. She is co-editor of Europa SF and currently teaches writing courses at George Brown College and the University of Toronto. Visit www.ninamunteanu.ca for the latest on her books.