Researchers at the Norwegian University of Science and Technology (NTNU) can say with confidence that a walk in the woods can help relieve symptoms of anxiety and depression. Writing in the journal Clinical Medicine under the title “A Systematic Review and Meta-Analysis of Nature Walks as an Intervention for Anxiety and Depression,” Associate Prof. Simone Grassini, who studies the evolution of the human brain and the interaction between humans and the environment, praised “forest therapy.”
“After a walk in the woods, your shoulders drop several notches,” Grassini wrote. “Your heart stopped pounding. Your thoughts flow a little more calmly. It simply becomes easier to relax. The world looks a little brighter. You aren’t alone in this experience. Many people need this therapy.”
Depression and anxiety are common mental health diagnoses. In Norway, approximately one in 10 people are estimated to experience anxiety or depression in the course of a year. These two often occur together. Worldwide, some 264 million people suffered from depression in 2020.
“After a walk in the woods, your shoulders drop several notches. Your heart stopped pounding. Your thoughts flow a little more calmly. It simply becomes easier to relax. The world looks a little brighter. You aren’t alone in this experience. Many people need this therapy.”
Associate Prof. Simone Grassini
His study at NTNU showed that in the era of smartphones and social media, the number of adolescents and young adults in his country who suffer from depression and anxiety has doubled. “Forty-four percent of teenage girls in Norway now struggle with stress and heavy thoughts,” he wrote.
How did he conduct his research?
Grassini collected all the studies that researchers around the world have carried out on this topic in the last decade. Then he started sorting, selecting all the studies that included a group that took walks in the woods and a control group that did not. Everyone in both groups struggled with anxiety and depression.
“These walks are an effective and simple method for something that a lot of people struggle with,” said Grassini, a neuroscientist and psychologist at the University of Stavanger. When the study was carried out, he was a researcher at NTNU.
“Is it the exercise itself that releases our mental knots? Or is it nature, with the stillness and rustle of the pines? Would it work just as well to just sit on a stump? Or is it the combination of exercise and nature that does the trick? Is a small outing enough or are forest trips necessary on a regular basis,” he wondered.
“No one has done a systematic analysis of the activity,” said Grassini, “because as we know, all research costs money, but we have some pieces of the puzzle. Lab studies show that even short exposures to images and videos of nature lead to a change in brain activity related to relaxation and well-being, and other research shows that exercise itself has a positive effect on the experience of well-being. Studies carried out outdoors have shown that even short exposure to a forest environment leads to less activity in the brain’s fear center.”
But no scientifically based method exists yet for how forest therapy should be carried out in concrete terms. Is one walk a week enough, or do you have to take four? Is half an hour enough or do you have to go for two hours?
“From a philosophical perspective, the results from studies of how being out in nature impacts us aren’t surprising,” concluded NTNU philosophy Prof. Solveig Bøe.
She points to the fundamental fact that humans are also part of nature. “If we go back far enough in our biological evolutionary history, we’re related to everything that lives and has lived.”
She believes that this explains why being out in nature feels meaningful – it can help us to realize that there is something more important than what we go around pondering in our hearts. “Out in green spaces, surrounded by birdsong, the sound of running water, the smell of vegetation, we understand that we are part of something bigger,” Bøe said. “It can do us good and help us to forget ourselves for a while.”