Forest baths can stimulate physical health, not just mental well-being

The so-called “forest bath” is known to have psychological advantages, including the reduction of stress and anxiety, but now research suggests that it also increases physical health by reducing blood pressure and inflammation.

Also known as Shinrin YokuJapanese forest bathing involves spending time in nature, generally while taking deep breaths and being aware of images, sounds and smells around you.

Iwao Uehara at the University of Agriculture in Tokyo and his colleagues wanted to better understand the advantages of this practice, so they looked 36 adults, aged 60 to 80, with high blood pressure.

Twenty-four adults spent three days and two nights in a forest framework in the Qianjiangyuan National Park, around 3.5 hours by car from the city of Hangzhou in China, where they participated in 3 hours of sweet hiking every day and a mindfulness meditation session of an hour group.

They also participated in an Qigong hour – a traditional Chinese exercise that uses slow and precise body movements with controlled breathing – every day, as well as an hour’s tea ceremony. These were made to help participants become more attentive so that they can be more submerged in the forest bath.

The researchers also made 12 people stay in the city and make a similar quantity to walk in the streets near their hotel, as well as a group’s mindfulness meditation one of the days.

The two groups followed the same activity and sleep hours and ate the same diets. They were also prohibited from using electrical devices, smoking and consuming alcohol or caffeine during the study.

The researchers measured the heart rate of participants, blood pressure and C-reactive protein levels, a marker of inflammation, before and after the intervention.

They found that those of the forest swimming group had considerably improved blood pressure and levels of C-reactive protein compared to the city group. They also had higher heart rate variability, a measurement of time variation between each heart rate, with higher scores linked to greater heart health.

“Forest therapy is inexpensive and reasonable therapy for people with high blood pressure,” said Uehara. Researchers believe that forest bath can calm the nervous system, helping to regulate heart and circulatory health.

The forest group has also reported greater reductions in anxiety and stress and improved energy levels compared to the city group.

But Julia Gohlke at Virginia Tech says that the study did not measure the number of steps that the two groups took. If the forest swimming group took more, it could explain the improved results.

However, the study supports the previous evidence showing the “decrease in physiological and emotional responses linked to stress by being in a forest framework”, explains Gohlke.