Sustainably managed forests play a major role in protecting the health of our planet, but did you know that forests can also play a role in protecting human health too? We take a look at some of the health benefits associated with being in and amongst trees.
There are a number of health benefits to being in the forest. These include:
Let’s take a look at how this is possible.
The idea that being in a forest can help concentration is based on a number of studies of people suffering from ADHD. A study conducted at the University of Illinois shows that children with ADHD demonstrate greater attention after a 20-minute walk in a park than after a similar walk in a downtown area or a residential neighborhood.
The study’s authors suggest that being in nature allows the brain to shift away from directed attention to fascination. That can allow people to recover from situational inattention and impulsivity (not necessarily ADHD-related).
“Directed attention fatigues people through overuse,” Dr. Stephen Kaplan says. “If you can find an environment where the attention is automatic, you allow directed attention to rest.”
That’s beneficial because we know too much directed attention can lead to attention fatigue, impulsivity, and distractibility.
Being in nature also has physiological benefits for our cardiovascular system. This has been proven by studies which have assessed the heart rates of people in woodland and urban environments.
A 2011 study into the relationship between physiological responses and physical environments in forest settings found that heart rate and blood pressure was significantly lower for a group that walked through a forest than it was for a group that walked in a city environment.
There is plenty of anecdotal evidence that walking through a woodland or forest can have a calming and restorative affect. I’m sure you know this from your own walks in nature. But what is the cause?
Dr. Qing Li, author of Shinrin-Yoku: The Art and Science of Forest Bathing and a medical doctor at Tokyo’s Nippon Medical School, explains: “There is real science behind these mood shifts, and there’s a chemical basis for the calming feeling we get from being among the trees.”
Apparently, it’s down to a variety of organic molecules that trees release into the air. Called phytoncides, these organic compounds have been shown to reduce levels of the stress hormone cortisol.
It seems natural that if forests can ease anxiety, they may have the potential to play a hand in beating depression.
That’s certainly suggested by one recent study that looked at the rate of antidepressant prescriptions and proximity to trees. It found that close proximity to trees (living within 100 meters) was linked with a lower rate of antidepressant prescriptions.
This can even help in urban environments. Research conducted in Leipzig found that street trees can help reduce the need for antidepressants among city dwellers.
It’s also worth noting that being outside in natural light can be helpful if you experience seasonal affective disorder (SAD), a type of depression that affects people during particular seasons or times of year.
Back to those organic compounds: phytoncides. As well as reducing stress, these compounds which trees naturally release into the air have also been shown to boost immune cell activity and decrease inflammation.
Ming Kuo with the Landscape and Human Health Laboratory, at the University of Illinois at Urbana-Champaign argues that these antimicrobial volatile organic compounds released by plants reduce blood pressure, alter autonomic activity, and boost immune functioning.
Other studies have shown this works better in forest environments than in urban areas. A 2009 study by Park et al. found higher levels of natural killer (NK) cell activity (a typical index of human immune function) in the human body when the subjects are in forest environments as opposed to when they are in urban environments.