Spending time in nature improves your mental health; New studies explain why

By Stacey Colino 

Doctors don’t usually prescribe spending time in nature to their patients but perhaps they should.

A robust body of research shows that being in green spaces — such as parks, woods, forests, mountains, and the like — is beneficial for people’s physical and mental well-being. Less well-known are the perks of hanging out around oceans, lakes, and rivers.

A report called Green and Blue Spaces and Mental Health issued by the World Health Organization shows that time in nature—including urban and peri-urban areas — improves moods, mindsets, and mental health. Research shows that exposure to forests, parks, gardens, or the coastlines can even mitigate the psychological impact of climate change, support physical activity, and provide opportunities for social interaction and places “to relax and leave daily stress behind for a while.”

In Singapore, greenery cascades off a luxury hotel, soothing guests in a balcony pool and people on the street below.

“If you think about our relationship to nature, it reminds us that we are embedded in the natural world, as a species,” says Patricia Hasbach, a psychotherapist and ecopsychologist in Eugene, Oregon. “We’re kind of returning home when we go into blue spaces or green spaces. It fosters a feeling of being part of something bigger than ourselves.”

There are many ways nature is beneficial for our psychological and physical health. A recent study surveying more than 16,000 people in 18 countries, found that people living in greener or coastal areas reported higher overall positive well-being. In addition, those who frequently visited green spaces or blue spaces (along the coast or inland) for recreational purposes felt better and suffered less mental distress.

Another study published last year in Occupational & Environmental Medicine found that people who visit green spaces five or more times per week have significantly lower use of psychotropic, antihypertensive, and asthma medications than those who spend less time in nature.

The mind-body benefits don’t stop there.

Restorative elements
While researchers haven’t done a head-to-head comparison of the perks of green versus blue spaces, there’s plenty of evidence supporting the mental-health benefits of both settings. Research has shown, for example, that the Japanese practice of “forest bathing” (a.k.a., Shinrin-yoku)—which involves slowly walking in a forest and inhaling the fragrant substances called phytoncides that are released by trees—reduces people’s blood pressure, alleviates depressive symptoms, and improves their mental health.

An analysis published last year, based on people from 18 countries, found that adults with better mental health, are more likely to report having spent time playing in and around coastal and inland waters as children. Earlier research found that people who live in homes with views of blue space in the city of Wellington, New Zealand, had lower levels of psychological distress than those whose homes have visible green spaces.

There are many possible biological mechanisms behind the perks of exposure to green or blue natural settings. One explanation is that these benefits likely stem from what’s called attention restoration theory, which proposes that exposure to nature helps relieve mental fatigue and improves ability to focus, explains Marc Berman, an environmental neuroscientist and associate professor of psychology at the University of Chicago. “Humans have two kinds of attention—directed attention, which is what we use at work and is the kind of attention that is fatigable or depletable, and involuntary attention which is automatically captured by interesting things in the environment and is not fatigable.”

Hikers take a break in the woods in Korea. Inhaling natural compounds like limonene and pinene while in a forest can decrease mental fatigue, induce relaxation, and improve cognitive performance and mood.

Indeed, a study in a 2019 issue of the journal Frontiers in Psychology found that after children took a 30-minute walk in a natural environment—with rolling grass fields, farmland, and forest areas—they had a faster, more stable pattern of responses to a series of attention-related tests than they did after walking through an urban area.

Besides capturing your involuntary attention, spending time in nature can elicit what’s called “soft fascination,” an unthreatening, pleasant experience that’s interesting but doesn’t require your full attention. This way, “your mind can wander and you can think about things at the same time,” Berman says. “When people are in nature, they tend to think about topics related to spirituality and their life journey.”

Another explanation for why nature has an almost medicinal effect on the mind and body is called the biophilia hypothesis, which suggests humans have an innate desire to connect with nature and other forms of life.

Smells, sights, and sounds, soothe our senses
In a natural setting, it isn’t just the blue and green colors that are soothing; the shapes of objects can be comforting, too, Berman notes. Research has found, for example, that looking at natural fractals—complex patterns that repeat at varying size scales in nature (ferns, flowers, mountains, or ocean waves)—induces more alpha wave activity in the brain (measured with electroencephalograms, EEGs), which is associated with a relaxed but wakeful state and internalized attention.

“When we’re in nature, we’re generally operating at a different pace,” says Hasbach, author of Grounded: A Guided Journal to Help You Reconnect with the Power of Nature—and Yourself. “It allows for sensory stimulation, allowing us to take in what we see, hear, smell, and feel. It helps us be fully present.”

In addition, “we associate natural sights and sounds with key resources—there’s an evolutionary basis for that,” says Amber Pearson, a health geographer and an associate professor in the department of public health at Michigan State University. “When birds are silent, that’s often a sign of danger. We may pick up on that.”

The flip side is true, as well: People find comfort in many sounds from nature. A meta-analysis that Pearson co-authored and published in 2021 examined the health benefits of exposure to natural sounds—from birds and animals, wind, and water—in national park sites and found that they were associated with reduced stress and annoyance, decreased pain, and improved mood. Water sounds were linked with the greatest boost on positive moods; while bird sounds had the most significant impact on reducing stress and annoyance.

Another noteworthy aspect of spending time in nature is what’s not there: traffic and noise. A review of studies, published last year in Environmental Research, examined the role of exposure to green spaces in preventing anxiety and depression in teens and young adults, ages 14 to 24. The most surprising conclusion? The absence of noise and the restorative qualities of green spaces promote mindfulness and interrupt harmful rumination. The exposure in turn reduces the risk of anxiety disorders and depression.

On another sensory level, researchers found that inhaling volatile organic compounds like limonene and pinene while in a forest can decrease mental fatigue, induce relaxation, and improve cognitive performance and mood.

When people spend time outdoors, it is often while walking, jogging, cycling, or gardening. In these cases, the combination of movement and natural scenery may double the benefits. For example, a study in a 2020 issue of the journal Environmental Research found that after office workers walked for 20 minutes per day in a blue space, they gained significant improvements in their mood and sense of well-being compared to walking for the same time in an urban space.

The nature prescription
While studies recommend at least two hours per week in green and blue spaces, “even a few minutes outside can improve mood and cognitive function,” says Eileen Anderson, a medical and psychological anthropologist and professor of bioethics at the Case Western Reserve University School of Medicine in Cleveland. “Remembering to take the small opportunities and soaking up longer times when possible can help your mind, body, and spirit.”

To that end, it’s a good idea to take “nature breaks” to regroup and refresh your mind — by walking in a nearby park or garden during your lunch hour, for example. While you’re there, tune in to the sights, sounds, scents, and other sensory experiences. “If you can find environments that don’t tax your direct attention and that stimulate your indirect attention, you can restore your attention and mental energy,” Berman says. “The more you can take breaks and go into nature, the better.”

To help yourself when you can’t get outside, you can bring elements from green and blue spaces into your home and reap similar benefits, Hasbach says. To that end, you can incorporate green plants and fractals (with a vase of flowers or a bowl of pinecones, for example) or photographs or paintings of scenes from nature or the coastline in your home. Similarly, you can bring aromas from the natural world indoors, with fragrant flowers or essential oils like lavender, rose, lemon, or rosemary.

If your home is near a wooded area, park, garden, or the ocean, consider opening your windows and inviting the soothing sounds of birdsong or waves in. If it isn’t, you can use an app to bring the sounds of birds, rain, the ocean or other elements of nature into your home, experts suggest.

“What’s especially promising is how dynamic the impact of the outdoors is on our brains,” says Anderson. “Even if nature has not been part of someone’s life, it’s never too late to add nature experiences to your life to improve well-being.”
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Credit: National Geographic