Do you ever get a feeling of calm while around trees, especially after a busy workday? As we spend more time indoors and on our devices these days, being in nature is a welcome break. But there is a chemical basis for the calming feeling we get from trees. It is a free, scientifically proven therapy known as forest bathing.

To practice it, you just need to be around trees and take in the environment, whether walking in the woods or having a picnic under a tree. The name derives from Japan, where it’s called ‘shinrin-yoku’. Nature-based therapy has existed there for thousands of years, but the term was coined in the 1980s when the Japanese government encouraged citizens stressed with work to walk in the country’s vast woodlands. Since then, it’s become popular across the world and studies on the health benefits have grown. Millions of dollars have been spent on research showing how walking in forests can improve our wellbeing.

Trees act as a kind of therapy

This is largely thanks to immunologist Dr. Qing Li, who fused the disciplines of medicine and the biology of trees to create forest medicine - pioneering this new form of medical science in 2012 by publishing the first forest medicine textbook. Li kickstarted a series of scientific studies that show forest bathing is not just ‘tree-hugging woo-woo’ (though hugging trees may not be out of the question!)

Having studied the effects of trees on our bodies and minds, his results show forest bathing reduces stress hormones, heart rate and blood pressure, while supporting metabolism, sleep and the parasympathetic nervous system which helps us rest and recover. Tests have also shown trees can boost anti-cancer proteins and natural killer cells that combat tumors.

But how? This isn’t just another mindfulness method. The sights and smells of the forest do contribute to these benefits, but the key ingredients are essential oils called phytoncides. These volatile, antimicrobial compounds are expelled from trees to protect them from invaders like insects and bacteria, and when we smell them, we can experience many health benefits.

Li proved the effects by exposing phytoncides in hotel rooms, measuring before and after effects on study subjects. Even while out of the forest, they experienced improved physical and mental health.

Now, forest bathing is studied by researchers across the world, from India and China, out to the west including the UK, Hungary, Poland, and Canada, revealing positive impacts on the immune system, heart rate, blood pressure, cardiovascular disorders and even addiction.

Studies are showing that trees lift our spirits by supporting our mental health and physical bodies, so it’s not surprising that forest bathing is now a scientifically prescribed treatment in some countries.

You don’t need to go to a forest in Japan to benefit, or even a forest at all. All trees have phytoncides. So, whether it’s a tree in the local park or your garden, you can breathe in this free therapy.