By Dr. Mercola
Many people feel an intrinsic pull to spend time in nature, and this makes perfect sense. Your brain and body are largely hard-wired to sync with the laws of nature — the rise and fall of the sun and the changing of the seasons, for example — not with the 24/7 work-a-day world.
So it's no wonder that when our senses get to take in nature at its finest — the sounds of a babbling brook, the scent of lush earth in a forest preserve or even the sight of a green oasis, a park, in the middle of a city — it sets off a cascade of benefits within our bodies.
In the video above, Leif Haugen, a fire lookout in a remote corner of the Flathead National Forest in northwestern Montana, shares what it's like to live alone in nature, which is an experience many of us living in the 21st century will never have.
In a world where 70 percent of the population will live in urban areas by 2015 (and more than half already do),1 it's become increasingly important to understand the importance of nature's presence in our lives, as well as what happens if we're separated from it.
City Living Linked to Anxiety and Mood Disorders
Researchers from the Douglas Mental Health University Institute at McGill University in Canada set out to determine whether changes in neural processes might be responsible for these findings.
They used functional magnetic resonance imaging (fMRI) to monitor the brains of 32 healthy adults asked to complete difficult math problems while being timed and hearing negative verbal responses.
Those who lived in urban environments had increased activity in the amygdala area of the brain, which is involved in emotions such as fear and responses to threats.
Those who lived in cities during the first 15 years of their life also had increased activity in the pregenual anterior cingulate cortex, which helps to regulate the amygdala.3 In short, those who grew up in an urban environment had a greater sensitivity to stress.
In an accompanying editorial, Daniel Kennedy, Ph.D., and Ralph Adolphs, Ph.D., both of the California Institute of Technology, explained that city living likely affects everyone differently, and your level of autonomy may play a role in how stressful it is for you.4
"There are wide variations in individuals' preferences for, and ability to cope with, city life: some thrive in New York City; others would happily swap it for a desert island.
Psychologists have found that a substantial factor accounting for this variability is the perceived degree of control that people have over their daily lives.
Social threat, lack of control and subordination are all likely candidates for mediating the stressful effects of city life, and probably account for much of the individual differences seen."
Nature to the Rescue
What else might affect your ability to thrive in an urban environment? Access to nature. A wealth of research points to the calming and healing effects of nature on the human body and mind.
For instance, research published in PNAS found that people who took a 90-minute walk in nature reported lower levels of rumination and had reduced neural activity in an area of the brain linked to risk of mental illness such as depression (the subgenual prefrontal cortex) than people who took a comparable walk in the city.5
"These results suggest that accessible natural areas may be vital for mental health in our rapidly urbanizing world," the researchers noted.
Other research has shown that even viewing images of natural scenery activates brain areas associated with empathy and altruism. In contrast, viewing urban scenes triggers blood flow to the fear-associated amygdala.6
"Shinrin-yoku," which is the Japanese term for "forest bathing" or spending time in a forest, is also said to benefit physical and mental health because you inhale beneficial bacteria, plant-derived essential oils and negatively charged ions via forest air.7
Living Near Nature May Extend Your Lifespan
In a study that followed more than 100,000 women, those who lived near higher levels of green vegetation had a 12 percent lower rate of non-accidental premature death compared to those living near areas with the least vegetation.8 Specifically, those living in greener areas had a:9
- 41 percent lower death rate for kidney disease
- 34 percent lower death rate for respiratory disease
- 13 percent lower death rate for cancer
The researchers suggested 30 percent of the longevity benefit may be due to nature's beneficial effect on mental health. Increased greenery may also affect lifespan by encouraging increased physical activity and social engagement as well as lowering exposure to air pollution.
Cognitive function may also improve. In a study of 2,600 children between the ages of 7 and 10, those with greater exposure to green spaces, particularly while at school, had improved working memory and decreased inattentiveness.10
In that case, a large part of the benefit (anywhere from 20 percent to 65 percent) was attributed to a reduction in exposure to air pollution as a result of the green spaces, but there's also past research that suggests "microbial input" from spending time in nature plays a role in brain development.11
A 2014 study similarly found that children attending schools with greater amounts of vegetation scored higher on academic tests in both English and math.12 Not to mention, older adults who spend more time outdoors have less pain, sleep better and have less functional decline in their ability to carry out their daily activities.13
4 Additional Benefits of Spending Time in Nature
Those living in a greener environment report fewer health complaints and better mental health.14 And all types of green space — city parks, agricultural areas, forest and others — were equally beneficial.
In addition, in the first systematic review on the health benefits of green spaces, it was found that living in greener environments is associated with better mental health and lower all-cause mortality.15 So if you can find even a few minutes a day to commune with nature, you'll likely reap great rewards, including:
1. Improved focus: Among children with ADHD, spending time in nature leads to improvements in focus and higher scores on concentration tests. Richard Louv, in his book "Last Child in the Woods," even used the term "nature-deficit disorder" to describe behavioral problems he believes stem from spending less time outdoors.16
2. Boosts in creativity: One study found walking increased 81 percent of participants' creativity, but walking outside produced "the most novel and highest quality analogies."17
3. A better workout: One meta-analysis of 10 studies found that physical activity outdoors for as little as five minutes leads to measurable improvements in mood and self-esteem.18 Levels of the stress hormone cortisol are also lower when people exercise outdoors as opposed to indoors.19
4. Less pain and better sleep: Older adults who spend more time outdoors have less pain, sleep better and have less functional decline in their ability to carry out their daily activities.20 According to research published in BioPsychoSocial Medicine:21
"The healing power of nature, vis medicatrix naturae, has traditionally been defined as an internal healing response designed to restore health.
Almost a century ago, famed biologist Sir John Arthur Thomson provided an additional interpretation of the word nature within the context of vis medicatrix, defining it instead as the natural, non-built external environment. He maintained that the healing power of nature is also that associated with mindful contact with the animate and inanimate natural portions of the outdoor environment.
… With global environmental concerns, rapid urban expansion and mental health disorders at crisis levels, diminished nature contact may not be without consequence to the health of the individual and the planet itself."
Even a Quick 'Nature Retreat' May Provide Physical and Mental Restoration
A study published in the International Journal of Environmental Research and Public Health (IJERPH) also highlighted the need for residents of urban environments to find relief from urban stressors, preferably by having access to outdoor open spaces. Researchers explained:22
"There is increasing scientific evidence that particularly open spaces with natural or vegetated elements, e.g., green spaces, provide opportunities for restoration.
Numerous … studies have shown that contact with real or simulated green settings as opposed to built settings has positive effects on mood, self-esteem and self-reported feelings of stress and depression, and can help to recover from stress and attention fatigue."
The study focused on the sympathetic and parasympathetic nervous systems, which handle stress either by triggering the "fight-or-flight response" or by enhancing physiological calm, respectively.23 Students wore sensors to track their heart rates and other functions and then viewed photos of green or urban spaces. The photos were shown both before and after the students conducted a serious of difficult math problems designed to raise stress levels.
When photos of green spaces were seen after the math test, the parasympathetic nervous system was activated and lowered heart rates. The researchers concluded:24
"This study indicates that five minutes of viewing urban green space can support recovery from stress as shown in enhanced parasympathetic activity. These findings strengthen and deepen the growing evidence-base for health benefits of green space in the living environment. In particular, the present findings point to the importance of visual access to green space in providing readily available micro-restorative opportunities."
Make Nature a Regular Part of Your Day
If possible, seek to spend time in nature daily. This could be something as simple as walking down your tree-lined street, tending to your backyard garden or eating lunch outdoors in a city park. When time allows, try to immerse yourself even more fully in nature by going for a hike in a nature preserve, canoeing down a river or even camping outdoors for a weekend.
Your body may dictate how much nature you need to feel fully recharged, so try to respect what it's telling you. Even a small dose of nature is better than nothing, and if you can't get outdoors to the real thing, even viewing nature photos or videos may help you buffer some stress.
You can also use the Emotional Freedom Techniques (EFT) to relieve the stresses of urbanized living. This may be especially useful for times when you're "trapped" in the city, but, once you learn it, you can even do EFT outdoors in nature for even greater healing effects.