I’ve always believed being out in nature had many psychological and physical health benefits. Time in nature is not just leisure time for me, it’s an essential investment in my health. Old-time therapies suggesting people with ailing health go for walks outside in forests or near the sea were not merely incidental advice, they were really onto something. Florence Williams, author of The Nature Fix writes, “Intuitively, many of us believe this to be true, that we feel better in nature. But it’s only recently that we’ve been able to see biomarkers of this change.” (1)  

Exposure to nature has been shown repeatedly to reduce stress and boost well-being, but scientists aren’t always sure why.

The early environmentalists advocated this idea. American writers such as Ralph Waldo Emerson and John Muir built a spiritual and emotional case to support their dreams for the creation of the first national parks in the United States, protecting spectacular places from logging, development and destruction. They firmly believed there was some element in nature which renewed and soothed the body. 

Often the best solution to a complex problem involves a simple premise. Nature has been perfecting the evolution of life for billions of years. It shouldn’t be a fantastic notion to consider nature may help to reverse ailments potentially caused by living disconnected from it. The empirical evidence mounts a strong case for ecotherapy (nature-as-medical-treatment). While nature is certainly not a cure-all panacea for all ailments, latest research reveals it does help and is an inexpensive and effective complementary tool to use in your arsenal for healing. 

Exposure to nature has been shown repeatedly to reduce stress and boost well-being, but scientists aren’t always sure why. There are many variables to consider. Studying nature’s health effects still an emerging field of science, largely led by Japanese scientists. The Japanese culture has been obsessed with creating a nature-civilization hybrid for thousands of years due to its perceived health benefits. Not unsurprisingly, the Japanese have the highest life expectancy of any country and many of its elderly citizens are healthier and more physically active in their twilight years than their peers in the west. Finland, another country with high rates of life expectancy, promote nature experiences as a crucial element in their public health policy.

Nearly a quarter of the Japanese population (between 2.5 and 5 million people) regularly participate in shinrin-yoku therapy—otherwise known as forest bathing—by walking in Japan’s 48 official forest therapy trails each year. People come from the city and shower in the greenery, with the aim of avoiding karoshi (death by overwork). Shinrin-yoku therapy is inspired by ancient Shinto and Buddhist practices where patients walk for extended periods through forested areas, at times sitting quietly, inhaling the scents, and letting nature enter the body through all five senses. Our senses evolved in the natural world, so it makes sense to bathe them in nature if we want to revitalise our health and also maximise vitality of the body. 

Forest therapy is attributed to Yoshifumi Miyazaki. Because humans evolved in nature, he believes it’s where we feel most comfortable even if we don’t always know it. He believes that because our physiological functions are adapted to it, a feeling of comfort can be achieved if our rhythms are synchronized with those of the environment. He believes nature’s profound impact on our cellular chemistry should have been studied 30-50 years ago. (2)

Miyazaki’s team in Japan compared forest walks with urban walks and detected improvements in stress, mood and anxiety. They discovered a 12.4% decrease in the stress hormone cortisol and a 7% decrease in sympathetic nerve activity in the forest walkers compared with those who walked in urban environments. (3) Miyazaki thinks our bodies instinctively relax in pleasant, natural surroundings because we evolved in such places. Basically, we feel relaxed in nature, because it feels like home to the biochemistry of the body.

Nature helps to recalibrate and invigorate all our five senses. To get the most out of nature the five senses should all be incorporated. The researchers in Japan found the phytoncide chemicals produced by trees play a role in improved health, and recommend we stop and smell the trees, because the invisible chemicals (called phytoncides) released from trees appear to have properties resembling a miracle drug. (4) 

One of Miyazaki’s collaborators, Qing Li, an immunologist in the department of hygiene and public health at Nippon Medical School in Tokyo, wondered if the improvements in NK cell counts during forest therapy was attributed to the aromatic volatile substances (scents) released by trees. Phytoncide derives from the Greek and Latin words for “plant” and “killer,” are antimicrobial compounds designed to ward off pests. At the low levels produced, we actually find them pleasant. 

Li’s team tested the theory by extracting essential oils from Hinoki cypress trees and used a humidier to send the steamed aroma into several hotel rooms. They then compared the results with a control group in other rooms who didn’t receive the scents. The phytoncide group had a 20% increase in NK cells and reported feeling less fatigue compared with the control group who exhibited no detectable changes. The scientists have now identified up to 100 of these phytoncides in the Japanese countryside, and virtually none are found city air except for low levels in areas surrounding city parks. Li is curious how we can bring nature into our urban lives and found a one-day trip in a suburban park had a marked effect, boosting both NK cells and anticancer proteins for an entire week afterward. (4)

The affects are not just on our sense of smell, but also our hearing and sight. Our senses are adapted to interpret information in a natural environment, not the artificial sounds in urban environments, which our physiology instinctively finds stressful. Modern technology is designed to catch our attention, but our brains are not designed for this kind of constant information bombardment. 

Our brain’s auditory system was designed to operate in natural environments. Continual, loud or unpredictable sounds activate the body’s sympathetic nervous system triggering an increase in stress hormones. The human auditory system is not adapted to live in the absence of sound either, which can also increase stress. Studies have found bird sounds, rainforest sounds, running water, wind or ocean sounds calm the nervous system and combat the release of stress hormones. The more natural the environment, the more restorative power it has.  

We can incorporate this knowledge to help decrease some of the stress while we undertake our urban responsibilities. I sit here typing this in a less than ideal downtown Vancouver city apartment—adjacent to an electrical substation—but to offset this, I often use an essential oil diffuser, which releases a refreshing blend of forest derived essential oils (such as pine, fir, cedarwood, eucalyptus etc). 

I often listen to nature sounds on my headphones to drown out urban noise. I sometimes look out my window at a nearby tree, and throughout the day I take a time out to look at nature photos. It is good to have a few nature landscapes to look at on your wall if you can do it. I found all these little tactics add up and help. For me constantly breathing in the smell of the forest as I work really helps to calm my indoor stress. 

However, there really is no replacement for being in nature, at least for a small part of our day. The simple act of going for a short walk in nature, allows the brain to go into a state of attention restoration, where circuits in the frontal lobes recover and return to a healthier baseline. The best results come from multi-day wilderness trips, allowing for a complete renewal in our brain as it shifts into a state producing persisting positive changes for cognitive function, mood and behaviour. (5)

One study related improvements of participants following a three-day white-water rafting trip. The researchers found a 30% reduction in post-traumatic stress disorder (PTSD) symptoms, a 20% reduction in general stress and a 10% improvement in social behaviour, life  satisifaction and happiness. (6) Markers for immune function also improved. Improved bursts of problem-solving and creativity are also noted. One study on hikers following a four-day backpacking trip, found they were 47% better at puzzles requiring creativity versus a control group of people waiting to go on the same trip. (7) Other anecdotal reports find emotional pain is significantly reduced after time in nature. One girl took her broken heart to the mountains, stating, “All I knew was that the mountains were where I felt the safest and calmest.” 

Evidence is mounting that to get the most out of nature, you really need to be present when you are in it. This is the most important factor of all.

Personally, I felt a similar experience. After suffering PTSD following two near death experiences, along with a financial disaster, I decided to continue on with a planned three-month car-camping trip in the Pyrenees and Alps of Europe. I was in a spiral of sadness, and had lost a lot of joy for life, but my visa in Canada had expired and as a travelling nomad at the time, I needed to go somewhere. I was worried about the trip, as I knew it would make my financial situation even worse, and I didn’t have much excitement about what was to come, since I would have to travel on a small budget. 

On the day I arrived in Paris, I collected my vehicle and had still made no decision which direction I would head. I had thoughts of going north to Holland, but I just started driving south. Ten hours later I was in the Pyrenees and had followed signs to the national park in Gavarnie. I didn’t really know what drew me in that direction. I didn’t know anything about Gavarnie before going, but immediately I saw the amazing sight of the majestic Cirque and its waterfalls. Poet Victor Hugo immortalised the place in his poem, Dieu, describing it as the colosseum of nature. I had never seen anything so dramatic and I knew I had been drawn to a place of immense healing power. I stayed for almost a week just drawing in the energy of the powerful nature in the region. I knew the nature was healing me. 

Subsequently, I spent the next three months exploring the Pyrenees and the alps in Switzerland and Austria, going from one beautiful place to the next. I felt truly like the mountains were healing me. When I returned from the trip, things got even worse in my life circumstances, but the anxiety or feelings of depression didn’t return anywhere near the intensity of what it was prior to the trip. I felt better equipped to handle my emotions and continued to move forward in life with a positive focus.

Here are a few key points on how connection with nature improves health: 

•  Faster healing. Exposure to nature can help us recover from surgery faster, require fewer medications, and have shorter overall hospital stays. 

•    Lowers cardiovascular stress. Researchers have noted lowered blood pressure, improved blood glucose, and lowered pulse rates after time in nature. 

•    Lower stress levels. Nature has distinct stress-reducing properties, helping to increase calmness and rebalance our emotions. Simply being in nature activates our parasympathetic nervous system, which calms and restores us. It also heals the two main stress systems, the sympatho-adrenal medullary and the hypothalamus-pituitary-adrenal axis. Cortisol, adrenaline and noradrenaline all drop after being within nature, but also fall when people visit an urban park or an urban woodland. The researchers in Japan conclude there’s something about being in nature that had a beneficial effect on stress reduction, above and beyond what exercise alone produces.

•    Increased life satisfaction, meaning and happiness. I’ve always found being in nature makes me feel happier. Some psychologists find connection with nature is a crucial missing piece in achieving better mental health due to its emotionally restorative capabilities. Nature appears to restore mental functioning in the same way that food and water restore our bodies. Simply being in nature is found to bring about positive emotions, a more positive outlook and promote general psychological well-being. Being in nature for as little as five hours a month makes you happier overall according to Finnish researchers. Furthermore, being immersed in majestic scenery can help remind us we are part of a world larger than ourselves. It puts life into greater context and perspective, making it more likely we will place higher value on intrinsic inspirations over material ones. Developing a fascination for nature, makes us more attentive to the environment when we are in it, which increases feelings of calm, rest and contemplation and overall sense of well-being. One study found the feelings of awe experienced in the presence of nature subsequently improved compassion, kindness and generosity.

•    Relieves anxiety and depression. One study found people who live in cities have a 40% higher risk of mood disorders compared to people in rural areas. (8) Researchers from Stanford University scanned the brains of people after a 90-minute walk in a national environment and found decreased activity in the subgenual prefrontal cortex, a brain region associated with negative thoughts (worry, anxiety and rumination etc…) which heighten the risk for depression and other mental illnesses. Rumination occurs when we get really sad, and we can’t stop thinking about the problem. If this occurs for too long, depression sets in. Nature walkers showed marked decreases in rumination compared with urban walkers. (9) Furthermore, walking in nature increases exposure to Vitamin D, which is known to help mitigate mental health issues. 

•    Increases in energy and vitality. Being outdoors gives us energy. Professor of psychology Richard Ryan explains we reach for stimulants like coffee when we feel depleted, but his research suggests a better way to get energized is to connect with nature. He says being outside in nature for just 20 minutes in a day can be enough to significantly boost vitality levels. (10)

•    Improved sleep. A two-hour walk in the woods is found to improve sleep quality and help mitigate sleep problems. Getting outside for most of the day—especially getting natural light when you wake up—helps to reset our circadian rhythms, improving symptoms in people with sleep disorders.

•    Increase in cognitive benefits. A walk through a park does wonders for a weary brain. Our brains aren’t tireless, they are easily fatigued. Scientists are finding more evidence being in nature has a profound impact on our brains and our behavior, helping to keep us psychologically healthy. It makes us better thinkers and improves creativity. According to Neuroscientist David Strayer, time in nature enhances higher-order thinking, restores attention, and boosts creativity. (11) One study found Outward Bound participants perform up to 50% better on creative problem-solving tasks after three days of wilderness backpacking. In multiple studies, time in nature significantly improved performance on memory, attention and cognition tests compared with indoor or urban environments. (12) Psychologists believe the constant demands of the modern world (particularly multitasking) burdens our brain reducing our effectiveness of higher-order thinking. Our brains can relax when we are in nature. Researchers at the Tel Aviv University found the sense of wonder and awe that arises from being immersed in grand lanscapes, enhances our expansive thinking. They determined nature switches on our outward thinking, breaking us out of the more dominant inward-focused mindset occuring with our habitual form of thinking. (11) The softer fascination and contemplative in-the-moment experience allows the mind to wander to explore the deeper aspects of memories and emotions, enhancing the imagination network in the brain. (11) 

•    Increases empathy and pro-social behaviors. People who regularly spend time outside demonstrate increased confidence, social skills, collaboration and empathy. (13) Time in nature appears to also have significant benefits for people suffering feelings of loneliness. (14) Lack of access to green spaces has been found to increase probability of violent behavior in people. 

•    Increased immunity. Nature boosts the immune system by increasing the amount of NK (natural killer) cells, a type of white blood cell that sends self-destruct messages to tumors and virus-infected cells. The researchers in Japan took a group of group of middle-aged Tokyo businessmen on a three-day stay in a forest, hiking both in the morning and afternoon. Blood tests showed an increased those natural cancer-fighting proteins and cell activity by a whopping 40%, and those proteins were found to remain elevated for 30 days following the forest visit, still 15% higher than before the trip. (15)

•    Illness Prevention and Longevity. Researchers find people who live closer to green space have fewer health complaints and live longer because the plant-life acts as a natural stress buffer. A survey for 3000 elderly residents in Japan, found those who lived near walkable streets and green spaces had lower rates of mortality overall. One research project even found spending time in nature may have a possible preventative effect on the development of cancer. The research says the closer you can live to trees, the better off you are. Air pollution now kills around seven million people every year globally, according to the World Health Organization, and trees are the biggest contributor to cleaning the air for us.

No one truly knows if there is an ideal amount of nature exposure, but longtime backpackers often say they need a minimum of three days to really unplug from their urban lives. However, even within a few minutes of being outside you can start feeling the benefits, so I think the goal is to get some nature time in every day if possible, or at least a few times a week. 

Tim Beatley, a professor at the University of Virginia—and his colleague Tanya Denckla-Cobb—endorse the habit of following the nature pyramid (modeled off the food pyramid), suggesting small doses of local nature on a daily basis, a weekly nature experience in a regional location, a monthly experience in a national park, and the occasional intense experience in the wild away from urban life once a year. Beatley writes, 

As adults, a healthy nature diet requires being outside at least part of each day, walking, strolling, sitting, though it need not be in a remote and untouched national park or otherwise more pristine natural environment. Brief experiences and brief episodes of respite and connection are valuable to be sure: watching birds, hearing the outside sounds of life, and feeling the sun or breeze on one’s arms are important natural experiences, though perhaps brief and fleeting. (16)

The pyramid represents inclusion of a diversity of nature experiences yields a healthy life, in the same way a diversity of foods and food groups leads to a healthy diet. (17)

Ultimately, you don’t need to know all of what the science reveals about how nature improves our health and our lives. Furthermore, we don’t need scientists to tell us going out into nature makes us feel better. I think we all intuitively know. Many of us will feel it when we are out there exploring our natural world. Evidence is mounting that to get the most out of nature, you really need to be present when you are in it. This is the most important factor of all. 

Bibliography
1. Nature Therapy Is a Privilege. [Online] 26 April 2019. https://www.theatlantic.com/health/archive/2017/06/how-to-harness-natures-healing-power/531438/.
2. Take Two Hours of Pine Forest and Call Me in the Morning. [Online] [Cited: 26 April 2019.] https://www.outsideonline.com/1870381/take-two-hours-pine-forest-and-call-me-morning.
3. Preventive medical effects of nature therapy. [Online] 26 April 2019. https://www.ncbi.nlm.nih.gov/pubmed/21996763.
4. Take Two Hours of Pine Forest and Call Me in the Morning. [Online] 26 April 2019. https://www.outsideonline.com/1870381/take-two-hours-pine-forest-and-call-me-morning.
5. Why Our Brains Need Multi-day Wilderness Trips. [Online] 26 April 2019. https://www.oars.com/blog/why-our-brains-need-multi-day-wilderness-trips/.
6. Warrior Adventures Canada Highlights Nature’s Way of Healing PTSD Sufferers. [Online] 26 April 2019. https://lbbonline.com/news/warrior-adventures-canada-highlights-natures-way-of-healing-ptsd-sufferers/.
7. How Nature Can Make You Kinder, Happier, and More Creative. [Online] 26 April 2019. https://greatergood.berkeley.edu/article/item/how_nature_makes_you_kinder_happier_more_creative.
8. Stanford researchers find mental health prescription: Nature. [Online] https://news.stanford.edu/news/2015/june/hiking-mental-health-063015.html.
9. How Walking in Nature Prevents Depression. [Online] https://www.theatlantic.com/health/archive/2015/06/how-walking-in-nature-prevents-depression/397172/) .
10. Spending Time in Nature Makes People Feel More Alive, Study Shows. [Online] http://www.rochester.edu/news/show.php?id=3639.
11. The New Science of the Creative Brain on Nature. [Online] https://www.outsideonline.com/2062221/new-science-creative-brain-nature.
12. Get Outside, It’s Good For Your Brain. [Online] https://www.scilearn.com/blog/cognitive-benefits-of-nature.
13. How nature can boost empathy imagination and well-being. [Online] http://www.educationthatinspires.ca/2017/08/21/forest-fridays-how-nature-can-boost-empathy-imagination-and-well-being/.
14. How nature can help people experiencing loneliness. [Online] https://www.wildlifetrusts.org/blog/dom-higgins/how-nature-can-help-people-experiencing-loneliness.
15. Effect of forest bathing trips on human immune function. [Online] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2793341/.
16. Exploring the Nature Pyramid. [Online] https://www.thenatureofcities.com/2012/08/07/exploring-the-nature-pyramid/.
17. Nature Pyramid. [Online] https://www.researchgate.net/figure/Conceptual-diagram-of-the-Nature-Pyramid-2012-Concept-by-Tanya-Denckla-Cobb-and_fig5_314236552.