Let’s face it – stress and unhealthy habits are ubiquitous in modern society. Equally ubiquitous (in affluent cultures) are self-help books, diet plans, personal trainers, and by-the-hour therapists to help people achieve and maintain their best selves. But what if one of the most potent fixes for our woes is as basic as spending more time outdoors, in nature?
That is the idea that Florence Williams explores in The Nature Fix: Why Nature Makes Us Happier, Healthier, and More Creative (2017, NY: W.W. Norton). As a journalist (and contributing editor to Outside magazine), Williams delves into the topic by taking a participatory journalism approach in which her experiences are part of the story. She becomes an insider in the scientific research she seeks to summarize about nature’s effects on the human mind, body, and spirit, both by becoming a research subject herself and by probing the thinking of leading scientists in the field.
She explains the impetus for writing the book succinctly: “Scientists are quantifying nature’s effects not only on mood and well-being, but also on our ability to think, to remember things, to plan, to create, to daydream and to focus—as well as on our social skills.” This work has such important implications for all of us that Williams makes an impressive effort to summarize the many avenues of this research being done around the world.
Williams reports on her experiences traveling to research sites in seven countries where scientists and practitioners are doing cutting-edge work on nature’s effects on people’s well-being. She participates in “forest bathing” in Japan and Korea; attends a hiking retreat with neuroscientists in Utah; wears a portable EEG device on her head to explore the physiological effects of noise pollution in the U.S.; participates in a nature virtual reality lab experiment in Canada; walks along “health nature trails” in Finland; participates in outdoor adventure therapy and meditative walking in urban parks in Scotland; observes horticultural therapy in a garden in Sweden; becomes a research subject for a Canadian scientist studying the mental health effects of sustained (30 minutes a day for 30 days) outdoor walking; goes on a camping trip with psychology graduate students in Utah and on a rafting trip in Idaho with female veterans suffering from PTSD to explore the effects of longer-term immersion in nature within social groups; visits a summer camp in North Carolina for kids with ADD and learning disabilities; and explores green spaces in densely populated Singapore. She is ambitious and energetic, and those qualities permeate the book.
Although the scientists Williams visits are focusing on different aspects of nature’s effects on humans, and are using a wide range of clever measurement tools to do so, an underlying theoretical tenet of all the research is evolution. Since we, Homo sapiens, evolved in nature, we still have deep, automatic, physiological reactions to environmental stimuli. The idea is to recognize, understand, and then use those reactions for beneficial outcomes in our modern lives.
Some Fascinating Research Findings
Japanese and Korean scientists have documented positive changes in physiological responses such as pulse rate, variable heart rate, and salivary cortisol after people have taken sensory walks in forested National Parks. In one study in Korea, spending two days in nature lowered the cortisol levels of 11-12 year old “technology addicts,” and those effects lasted two weeks after the kids had nature immersion experiences.
Another avenue of this “forest bathing” (i.e., walking in the woods) research found that “nice tree smells”—specifically the aromatic substances that cedar and pine trees emit—boost natural killer (NK) white blood cells that strengthen our immune systems. Even a month after people walked in piney woods a few hours a day for three days, their NK cells were 15% higher than those of people who walked the same amount of time on urban streets.
In addition to affecting us through our sense of smell, nature also triggers profound effects through our visual system. One of the reasons that spending time in peaceful natural settings can improve our ability to think effectively and creatively is that we don’t have to use up as much precious cognitive fuel (specifically oxygenated glucose) filtering out distractions. Our inherent “soft fascination” with natural scenes gives our brains a rest so we have the potential to become better at higher order thinking.
Even brief views of nature, such as seeing green trees out a window, can have positive effects on our bodies and minds. One hypothesis is that visually processing nature scenes triggers natural opiates in the brain and “happy molecules” flow. Indeed, studies have shown that nature views outside hospital windows reduce patient stress and lead to better clinical outcomes. In schools, office buildings, and housing projects touches of nature visible from windows have been shown to support increased worker productivity, less job stress, higher academic grades and test scores, and less aggressive behaviors. Scientists propose that this is due in part to congruence in how nature scenes (“natural fractal patterns”) are fluently processed by our neurons, setting off a cascade of positive physiological effects.
In short, Frederick Law Olmstead (the father of landscape architecture and designer of urban parks such as New York’s Central Park) seems to have had it right back in 1865 when he wrote that viewing nature “employs the mind without fatigue and yet exercises it; tranquilizes it and yet enlivens it; and thus, through the influence of the mind over the body, gives the effect of refreshing rest and reinvigoration to the whole system.”
Our sense of hearing also has deep evolutionary roots, so ambient nature sounds trigger very different automatic responses in our bodies than industrial noise. Our sympathetic nervous system (the coordinator of our “fight or flight” responses) reacts dramatically to threatening sounds by elevating heart rates, blood pressure, and respiration. Those are stress responses, and when we’re constantly subjected to annoying noises, everything from airplanes and jack hammers to cell phone ringers and lawn mowers, those frequent stress responses can accumulate to the level of chronic stress within our bodies.
Given that there are fewer than a dozen sites in the continental U.S. where you can’t hear human-made noise for a span of at least 15 minutes (according to research conducted by an acoustic ecologist), this lack of respite from industrial noise can become a major health issue. For instance, every 10-decibel increase in nighttime noise is linked to a 14 % rise in hypertension. In primary schools located near major airports, every 5-decibel increase in aircraft background noise is linked to a drop in reading scores equivalent to a two-month delay in progress.
There are individual differences in people’s noise sensitivity, and Williams found that she is among the most sensitive. She wore EEG headgear to measure her brain wavelengths in different settings to see which places put her brainwaves in the desirable, meditative-like state of “calm alert.” In places where human-made sound is constantly in the background, our brains have to work hard to ignore the irrelevant soundscapes, stealing physiological resources and constantly creating undesirable small side effects. So it is hard for someone with noise sensitivity (like Williams) to unwind in an urban park. After numerous forays outside, Williams finally attained Zen-like brain wavelength tranquility one early morning while kayaking alone on a lake in Maine. The take-home message is that when you’re feeling stressed, go to a quiet place to reset your mind and body to a calmer mode.
In addition to documenting nature’s profound influence on our physiology, Williams also reports on how it can affect our emotional well-being. A researcher in Finland recommends that to elevate mood and stave off depression, people should spend a minimum of five hours per month in nature, and that 10 hours per month yields even more positive results on emotional stability.