No claw-footed tub in the woods needed or romantic shower under a waterfall. (Sorry to disappoint… as I love the idea of both) Forest bathing, as it has been dubbed, is actually a studied medical practice. In Japan, the research is spawning a whole new dimension of patient treatment called “forest therapy.”

Forests, like other wild settings, engage our senses in more subtle but evolutionarily familiar ways than our typical modern environments. Sounds in nature are quieter but more subtly layered. Our sight is more expansive. Our sense of touch, finer. Our smell, more acute. Surrounded by nature, our perception reorients to its default setting. Asn increasing amount of research shows just how “natural” time in nature is for our physiological and psychological well-being. Exposure to green space offers protective factors against depression and anxiety and overall sense of wellbeing. Instinctively, we know this and have likely experienced it. When we step outside our commotion-filled, asphalt-coated environments and truly inhabit a wild space, we’re more relaxed, more at peace. The mind finds quiet and the soul, release.

Yet, the research behind forest bathing takes all this a dramatic step further. Time in a wild setting, studies indicate, unleashes a powerful cascade of hormonal and cellular responses. Salivary cortisol, for example, dropped on average 13.4% when subjects simply looked at a forest setting for 20 minutes. Pulse rate, blood pressure and sympathetic nerve activity decreased as well. Even more remarkable is the significant – and lasting – impact on so called “natural killer” cells, powerful lymphocytes known to fight off infection and attack cancer growth. A longer three day trip in the forest with daily walks resulted in a 50% rise in NK activity as well as an increase in the number of NK cells! The forest exposure, researchers found, also resulted in increased anti-cancer protein expression. Tests further indicated a rise in the levels of intracellular granulysin, perforin, and granzymes A/B and a decrease in urinary adrenaline. What’s perhaps most surprising is this: subjects who participated in this series of forest bathing trips showed immune NK benefits that lasted more than a month. This finding, the researchers suggest, indicates the protective benefit of a monthly trip to the forest environment. (Have any weekend plans?) Yet, additional studies suggest that part of this immune boost is attributable to phytoncides, wood’s essential oils. Score on for aromatherapy. It’s interesting food for thought.

As a result of these studies, government entities in Japan are partnering with the medical industry to hold free health checkups at park areas and to create designations for “official” forest therapy sites. Finally, more companies are opting to include forest therapy in health care plans.