Many people feel calmer after walking through a park or sitting beneath a tree. Scientists are increasingly finding that this feeling is supported by research.
Spending time in nature appears to benefit the brain, heart, immune system and mental wellbeing in ways that modern medicine is only beginning to understand.
These findings were highlighted through Harvard Medical School, where physician Susan Abookire teaches forest therapy to healthcare workers experiencing stress and burnout. Her sessions encourage participants to slow down and pay close attention to nature instead of rushing through it.
The idea comes from Japan, where forest bathing has been practised for decades. Rather than focusing on exercise, people simply walk slowly, notice colours, sounds, textures and smells, and avoid distractions such as mobile phones. Researchers believe this mindful approach may help explain many of the health benefits that have been reported.
Trees release natural oils known as phytoncides. Japanese studies have shown these compounds may stimulate natural killer cells, an important part of the immune system. Scientists are also investigating fragrant plant chemicals called terpenes because laboratory research suggests some may reduce inflammation and support brain health.
Nature appears to help the brain recover from mental fatigue. Long hours spent concentrating on computers can tire areas of the brain involved in attention and decision-making. Research suggests natural environments help restore focus, creativity and memory by giving these brain systems a chance to recover.
Stress reduction is one of the strongest findings. Studies measuring cortisol before and after forest walks have repeatedly found lower levels after time outdoors. Reduced stress may also help lower blood pressure and improve overall emotional wellbeing.
Researchers have reported improvements in sleep, heart health and breathing after spending time in forests. Some studies even suggest that listening to birdsong or looking at natural scenes may activate relaxation pathways inside the brain.
Interestingly, benefits may still occur even when people cannot enter a forest. Research has shown hospital patients with views of trees often recover more quickly than those looking at brick walls. Green roofs and pictures of natural landscapes have also been linked with better attention and mood.
Despite these encouraging results, scientists caution that not every study reaches the same conclusions and many have involved relatively small numbers of participants. Larger studies are needed to determine the ideal amount of time people should spend in nature and which environments provide the greatest health benefits.
Overall, the evidence supporting nature as a health intervention continues to grow. The strongest aspect of this body of research is that many independent studies report similar benefits across mental and physical health.
The main weakness is that researchers are still learning exactly how these effects occur. Even so, taking regular walks in parks, forests or other green spaces appears to be a simple, safe and affordable habit that may improve quality of life for many people.
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Source: Harvard Medical School.
