Terpenes & Phytoncides -
Discover The Little-Known Health Benefits of Trees

Forests are not only one of our last refuges of clean air, a place where we can escape the pollution that cars, chimneys, planes, and so many other things impose on us every day. They are also a priceless treasure box of terpenes and phytoncides.²Characteristics and distribution of terpenes in South Korean forests | Journal of Ecology and Environment [Accessed 27th August 2021] A variety of plant-produced substances fall into these categories, and other plants, besides trees, emit them as well. Yet, in a forest, you get the maximum effect of these little miracle workers. Plants have developed terpenes and phytoncides for various reasons. They help to deter herbivores and attract beneficial animals instead. But terpenes and phytoncides also help trees to heal themselves. And would you have guessed that trees can even communicate with each other using these natural chemicals, for example, to warn their neighbours about an attack of an insect or another herbivore?

Some of them also have a very positive effect on our health and mental wellbeing. So far, scientists have discovered more than 80,000 terpenes, and they suspect there are many more. Some of the known terpenes are produced by animals, but most of them are emitted by plants.³What to know about terpenes | MedicalNewsToday [Accessed 26th August 2021]; Phytoncides: The Science Behind Forest Bathing Benefits | Forest Bathing Central [Accessed 26th August 2021]; More is better: the diversity of terpene metabolism in plants, Fei Zhou & Eran Pichersky, Department of Molecular, Cellular, and Developmental Biology, University of Michigan | Science Direct [Accessed 26th August 2021] So, let’s find out what they can do for you!

Surprisingly, terpenes and phytoncides⁴Phytoncides: the language of the trees? | Sense in Nature [Accessed 26th August 2021]; see also Phytoncide | Wikipedia [Accessed 26th August 2021] and Terpene | Wikipedia [Accessed 26th August 2021] do not only protect plants from harm but also us humans. They are bioactive, which means they cause our bodies to react to them. One of their predominant effects is how they act upon the human immune system. Science has shown that people who spent time in a forest had significantly more natural killer cells in their bodies.⁵Effect of forest bathing trips on human immune function – Scientific Study by Qing Li | National Center for Biotechnology Information [Accessed 26th August 2021]; Effect of Phytoncide from Trees on Human Natural Killer Cell Function | Q. Li, M. Kobayashi, Y. Wakayama, Hirofumi Inagaki | ResearchGate [Accessed 26th August 2021] Natural killer cells are your bodyguards against any germs or viruses that might enter your system. The more you have of them, the better your chances of staying healthy.

There is only a tiny catch to it. Usually, conifers emit more healthy terpenes and phytoncides than broad-leaved trees. If, however, trees are planted in climate zones where they don’t belong, things change.⁶Peter Wohlleben, The Hidden Life of Trees, in the German edition: Das geheime Leben der Bäume (Hardcover), Ludwig Verlag München, 10th Edition, 2015, p.198f. Some conifers such as spruces and Scots pines naturally belong into nordic regions and not into countries such as, for example, Germany – but in this country, the majority of trees are, as you might have guessed, spruces and Scots pines. By 1800, most of Germany’s forests were gone, cut down by the growing population, which needed more and more wood and space. During times of war, even more wood was needed. When reforestation began, people planted mostly spruces and Scots pines instead of native broad-leaved trees.⁷Historical evolution of forest management in Europe and in Japan | Alessandro Paletto, Cristina Sereno, Hiromichi Furuido | ResearchGate [Accessed 26th August 2021]; The prehistoric and preindustrial deforestation of Europe, Jed O. Kaplan, Kristen M. Krumhardt, Niklaus Zimmermann, Quaternary Science Reviews | Eidg. Forschungsanstalt für Wald, Schnee und Landschaft WSL [Accessed 26th August 2021]; Forest dynamics in Europe and their ecological consequences | European Environment Agency [Accessed 26th August 2021]; History of the forest in Central Europe | Wikipedia [Accessed 26th August 2021] They grow faster and supposedly produce more wood, and thus, profits. But even back then, Germany’s climate was too warm and dry for spruces and Scots pines, and today things are even worse due to climate change. During the summers, these trees have been in great distress, especially in recent years. Summers are becoming hotter and drier than ever around the globe, so distressed trees are not a problem of only Germany anymore.⁸Trees and Climate Change | FORECCAsT [Accessed 27th August 2021]

Trees in distress send out terpenes and phytoncides as well, but different types than healthy trees. As Peter Wohlleben, a renowned tree expert, writes in his book, “The Hidden Life of Trees,” these trees are always close to dying from heat and lack of water. This also makes them prone to attacks from parasites, and they “cry out” by sending out terpenes and phytoncides to “inform” their neighbouring trees about the danger and stress that comes with it. Experiments have shown that these types of terpenes and phytoncides can also adversely affect humans. For example, if you stand under a tree in distress, your blood pressure may rise. On the other hand, if you stand under a healthy tree, your blood pressure becomes lower.⁹Peter Wohlleben, The Hidden Life of Trees, in the German edition: Das geheime Leben der Bäume (Hardcover), Ludwig Verlag München, 10th Edition, 2015, p.199 So, head out into the woods to get your dose of health-boosting terpenes and phytoncides, but inform yourself first which trees are native to your area and where to find them – and tell everyone you know how important it is to keep trees healthy.

In 1982, the Japanese government introduced “forest bathing” (“Shinrin Yoku” in Japanese) to encourage Japanese citizens to spend more time in nature and harness its positive impact.¹⁰‘Forest Bathing’: How Microdosing on Nature Can Help With Stress | The Atlantic [Accessed 27th August 2021]; Shinrin-Yoku: The Japanese art of forest bathing | Japan Today [Accessed 27th August 2021]; The physiological effects of Shinrin-yoku (taking in the forest atmosphere or forest bathing): evidence from field experiments in 24 forests across Japan | Bum Jin Park , Yuko Tsunetsugu, Tamami Kasetani, Takahide Kagawa, Yoshifumi Miyazaki | PubMed [Accessed 27th August 2021] Since then, the therapeutic effects of trees have even made their way into medicine. For example, rehabilitation hospitals in Bavaria have started to incorporate forest bathing into their care programs.¹¹Pilotprojekt in Bad Wörishofen: Bayerns erster Kur- und Heilwald | Kurier [Accessed 27th August 2021]; Projekt „Wald und Gesundheit“ des Bayerischen Heilbäder-Verbandes startet in 14 bayerischen Heilbädern und Kurorten | Bayerischer Heilbäder-Verband e.V. [Accessed 27th August 2021] It’s not just the easily curable things trees help curing. Spending time in forests speeds up healing processes after surgery, and there have been several studies that have shown the anti-cancer effect of terpenes in both in vitro and in vivo in mice.¹²Terpenoids: Natural products for cancer therapy | Min Huang, Jin-Jian Lu, Mingqing Huang, Jiao-Lin Bao | ResearchGate [Accessed 27th August 2021]; 4 Terpenes Known To Have Anti-Cancer Properties | Lab Effects [Accessed 27th August 2021]; Terpenoids as potential chemopreventive and therapeutic agents in liver cancer | Roslin J. Thoppil, Anupam Bishayee | National Center for Biotechnology Information [Accessed 27th August 2021]

Connecting to nature is essential for being happy and for maintaining a balanced life. Many of us have lost this connection or don’t maintain it regularly. Being outside in nature stimulates your body to produce more of the hormones that make you happy. Remember that everything is connected. Everything is part of the same universal mind, and everything has an energy that vibrates at a specific frequency. Trees are powerful beings. Some have been around for hundreds of years or even longer (a few even in Germany). Hug a healthy tree or at least touch it or lean against it, and you will feel some of that energy flowing through you. A tree in distress surely would appreciate a hug as well, but healthy trees seem to have a more positive effect on our happiness than trees fighting for their lives. Peter Wohlleben suggests that this again is due to the different types of terpenes and phytoncides they emit. In my opinion, purely energetic vibration plays an additional role. Just imagine how it feels when you are comforting a sick cat or dog. Although you love it, the vibrations it gives off don’t make you happy but rather sad because you feel with them and worry about them. This doesn’t mean that you shouldn’t hug a sick pet or a distressed tree. It only means that, in this case, you should reverse the energy flow. You should place yourself in a positive mindset and be the one sending out positive vibes to the being in need instead.

At a hospital in Philadelphia, doctors discovered that even the sight of trees speeds up healing and recovery. Patients who were given a room with a view of trees recovered much faster than patients with rooms facing buildings. They also had much fewer problems with depression after surgery.¹³View through a window may influence recovery from surgery | R.S. Ulrich | National Center for Biotechnology Information [Accessed 27th August 2021] So, if you are about to move houses, you might want to pay attention to where your new home is located. The best thing would be to move out of the city. In any case, at least try to have some trees in front of your living room window.