Shinrin-Yoku: Pliny's Pine Groves to Japan's 1982 Forest Bathing Policy

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In antiquity Pliny the Elder advised patients with lung complaints to visit pitch-producing pine forests rather than take a sea voyage, and in the Middle Ages people used conifer forests to treat pain and bronchial problems through terpenoids like camphor and turpentine. The formal practice began in Japan in 1982, during an economic bubble marked by urbanization and long working hours. Tomohide Akiyama, director of the Ministry of Agriculture, Forestry and Fisheries, introduced the term shinrin-yoku, or forest bathing, to relieve stress and build public support for protecting the country's forests, drawing on early research into phytoncides, the antimicrobial compounds plants release.

The practice calls for a slow pace, no electronics and deliberate use of all five senses. Studies report increases in natural killer cells, lower pulse, blood pressure and cortisol, and improved mood scores after one to three hours. Skeptics remain. Georges Plaisance's 1985 book Forêt et santé was largely personal reflection, a 2023 broadcast by Swiss network RTS said the mechanisms are poorly understood, and Le Figaro argued the benefits may come from slow walking, deep breathing and a cultural placebo rooted in Shinto and Buddhist reverence for nature.

• A 2021 South Korean study of weekly sessions over eight weeks found lasting stress reduction and better sleep compared with an urban control group.
• Researchers describe a cocktail effect, in which phytoncides, gentle movement and distance from city stimuli act together.
• South Korea opened its first therapeutic forest in 2009 and had 32 by 2020.
• Finland's Forest Association offers guided recovery activities aimed at restoring body and mind.
• The U.S. Forest Service runs two-hour sessions with certified guides in Puerto Rico's El Yunque rainforest.