Scientists have known for a long time that taking a walk outdoors can do wonders for your mental health. But until now, they didn’t know exactly why.
A new study published in Molecular Psychiatry has found some of the first causal evidence for the mental health benefits of walking by showing that a 60-minute walk in nature leads to a reduction of stress-related markers in the brain.
To learn more about the relationship, researchers from the Lise Meitner Environmental Neuroscience Group at the Max Planck Institute for Human Development recruited 63 volunteers and asked them to either take a walk in nature (in this case, a forest) or in an urban setting.
MRI scans were used to record brain activity before and after walks, looking for markers of stress through activity within the amygdala. Considering the important role of the amygdala in processing emotions and fear, which has previously been shown to be more active in people living in cities than those living in rural areas, it can be said that it acts as an important marker for stress.
Following the nature walk, participants were found to show lower amygdala activity, suggesting that walking reduces stress levels and may counteract the negative effects of urban origin.
“The results support the presumed positive relationship between nature and brain health, but this is the first study to prove a causal link. Interestingly, brain activity in these regions remained stable and did not increase after urban walking,” Simone Kühn, head of the Lise Meitner Environmental Neuroscience Group, said in a statement. “This goes against the common view that urban exposure causes additional stress.”
The results could have a significant impact on how we deal with mental health issues and even how residential spaces should be designed in the future, as previous studies have shown strong links between living in cities and mental health disorders. Access to green spaces can create a barrier between urban-related stress and even protect against risk factors for mental health problems if more mechanisms are uncovered.
Along with previous studies suggesting that people who live in the countryside or have access to forest have healthier amygdala structures, science does indeed seem to encourage you to venture out into the wild. Brief exposure to a natural environment can help offset the effects of concrete forests, and places like Canada are taking advantage of this data by issuing National Park passes for people with depression or anxiety.