By Jody McCutcheon
A couple of years ago, a UN report proclaimed that for the first time in history, more than half the human population inhabits cities. But from a health perspective, maybe it’s time we returned to the forest.
Compared to the drab concrete jungles slowly choking our planet and depleting our natural resources, forests are like medicine for our ailing bodies. A plethora of evidence suggests that the impact of forests on human health may be stronger than we think; a walk in the woods (or more generally spending time outside in nature) provides real, quantifiable mental and physical health benefits. And you needn’t go out for long. Even just a five-minute walk in a forest, park or garden will do.
Sound too good to be true? It’s not. In fact, the practice of walking through a forest to fix what ails us has been around for centuries. In 1982, the Japanese Ministry of Agriculture, Forestry and Fisheries even gave it a name: shinrin-yoku. Basically, this means “forest bathing,” but as this study mentions, a less poetic translation might be “making contact with and taking in the atmosphere of the forest.”
While it may have been named in 1982, shinrin-yoku is based on ancient Shinto and Buddhist practices surrounding the idea of “letting nature enter your body through all five senses.” Essentially, the goal is simply to get away from the stresses of life, slow down, take a breather, unplug from the devices that rule our lives. Sit and gaze at trees, relax, inhale the forest air. Considering our nervous system is both a product of and in synch with nature, it seems to make sense that forest bathing affects our health in myriad ways.
The Japanese government has invested plenty of resources into the practice. In the last decade, they’ve sunk at least $10 million into shinrin-yoku research and established official “forest therapy” sites. And that part of the world doesn’t see it as a casual form of alternative treatment, either: in both Japan and Korea, forest therapy is covered by health insurance. These countries are talking the talk and walking the walk.
Specific Health Benefits
Disagreement exists over how shinrin-yoku produces its positive health effects, but there is no shortage of theories. For example, some researchers attribute its benefits to a sense of awe we feel when viewing the breathtaking landscapes nature’s palette has to offer. Consider the awe astronauts experience upon seeing Earth from space. A forest walk may not inspire quite the same sensation, yet feelings of awe have nonetheless been linked to improved health markers.
Being surrounded by trees and nature also has proven benefits for children – for example, children who play outside around trees demonstrate improved moods, reduced depression, and also reduced mental fatigue. More outdoor time in nature also improves vision and reduces body inflammation.
While science hasn’t pinned down the exact mechanism underlying shinrin-yoku’s efficacy, no shortage of research supports the practice and its impressive list of benefits: enhanced immune system and energy levels, reduced blood pressure and stress levels, improved mood, sleep and the ability to focus (even in children with ADHD). Shinrin-yoku also accelerates recovery time from surgery and illness. Some further benefits are detailed below:
Enhanced Immune System
As we inhale fresh forest air, we breathe in phytoncides, which are essential oils that plants emit to protect themselves from insects and decay. Phytoncides possess antibacterial and antifungal properties that help flora ward off disease. When we inhale these chemicals during our woods walk, our bodies increase the number and activity of a type of white blood cell called natural killer (NK) cells, which snuff tumour- and virus-infected cells in our bodies. At least one study shows that a 3-day, 2-night forest-bathing sojourn stimulates an increase in NK cell activity that can last over 30 days. Japanese researchers continue to investigate whether Shinrin-yoku helps fight certain types of cancer.
1. Reduced Stress, Lower Blood Pressure, Improved Mood
Plenty of studies (e.g., here, here, here, here) indicate that exercising in forests or simply sitting in them and looking at trees reduces pulse rate, blood pressure and the stress-related hormones cortisol and adrenaline. How? By promoting more parasympathetic nerve activity (rest-and-digest) at the expense of sympathetic nerve activity (fight-or-flight), Shinrin-yoku makes people feel more rested and at ease. Even just looking at pictures of trees can relieve stress, although to a lesser extent. At the same time, a walk in an urban, unplanted area produces none of the same stress-reduction benefits. And since stress inhibits our immune system, the stress-reducing benefits of Shinrin-yoku further enhance immune system functioning.
Furthermore, researchers using the Profiles of Mood States (POMC) test found that Shinrin-yoku reduces anxiety, depression, anger, confusion and fatigue. And a recent Stanford study discovered that a walk in a park reduces blood flow to the section of the brain linked to brooding. If that’s not enough, researchers claim brooding is a mental state found more frequently among urbanite populations. This evidence suggests Shinrin-yoku is something of a natural mood enhancer.
2. Improved Focus
(Post)modern life is busy! In balancing work, school, family, etc., we often have too many things to focus on at once, which can leave us with little energy to spread around, never mind devote to a single task over a long period of time. This phenomenon is called Direct Attention Fatigue. Shinrin-yoku gives the cognition part of our brain the break it needs to recharge energy levels, refocus and renew our sense of patience.
3. Improved Attention Span And Impulse Control
Attention fatigue affects the prefrontal cortex, which is the part of our brain affected by Attention Deficit/Hyperactivity Disorder (ADHD). Studies (e.g., here, here) indicate that children who spend time outdoors in nature show reduced attention fatigue, and ADHD-diagnosed children who spend time outdoors in nature show a reduction in related symptoms. Researchers are investigating the use of Shinrin-yoku in ADHD-management approaches. If successful, this strategy would offer the added value of being inexpensive and widely accessible, with no side effects.
4. Accelerated Recovery Time From Surgery And Illness
Window views of vegetation and especially water can fast-track recovery from illness and surgery. Studies like this one show that post-operative patients staying in rooms offering “green” views, as opposed to those with no view or a view of a brick wall, experience shorter post-op stays and slightly fewer post-op complications while taking fewer painkillers.
Fewer Trees Equals Poorer Public Health?
Following the logic that exposure to trees boosts health, evidence suggests a reduction in trees may lead to poorer health and related outcomes. Take the case of the emerald ash borer (EAB), a wood-boring beetle that kills ash trees within three years of infestation. Since it was first detected in North America in 2002, the EAB has decimated ash populations, a development sad enough in itself. But the story gets worse. A study looking at human deaths from lung and heart disease found an additional 6,113 lung disease–related deaths and 15,080 heart disease–related deaths in EAB-affected areas, compared to normal death rates. Perhaps if those trees hadn’t been destroyed, some of those deaths could have been avoided.
It’s also important to note that the benefits of forest bathing only come from natural forests – which is worrying, given the proliferation of GMO trees. This issue is something that few of us are aware of, but if GMO forests are allowed to continue further, this could have a profoundly detrimental affect not only on wildlife, but our own health, too.
Valuable Healthcare Strategy
Following in the footsteps of other popular Eastern health trends like yoga and meditation, shinrin-yoku has been proven to be a valuable healthcare strategy that shouldn’t be ignored. Many businesses are capitalising on the growing popularity of forest bathing. You can do it with a group in a company-guided forest tour, or take your own nature walk on a preferred route, depending on your preference.
And if you live in a city, like more than half of us now do, no worries. Just visit an urban park or garden, or take a walk down a tree-lined street. These pockets of urban green spaces are known as the “urban and community forest,” and they offer all the benefits of rural forests. But if you can, it’s always nice to get out of the city, away from the bustle and concentrated pollution, and surround yourself with nature. Your body and soul both seem to know it, too.
All images Wikicommons except main image, All-free-download.com