Eine japanische Studie konnte im Jahr 2007 zeigen, dass ein Aufenthalt im Wald "Shirin-Yoku" -die Atmosphäre des Waldes aufnehmen & Waldbaden- positive physiologische Effekte hat: es kann den Blutdruck sowie das Stresshormon Cortisol im Blut senken, zur Körperentspannung beitragen und das Immunsystem stärken, indem die natürlichen Killerzellen aktiviert werden. Damals nahmen 12 Personen an der Studie teil. Referenz: Li, Q. et al. (2007). Forest bathing enhances human natural killer activity and experssion of anti-cancer proteins. Int J. Immunopathol Pharmacol 20: 2-8. Dies wurde in weiteren Studien repliziert, beispielsweise mit 280 Studienteilnehmenden (Bum Jin Park et al., 2010). Verschiedenste Resultate zeigten immer wieder, dass Waldbaden gesundheitsförderlich sein kann.  

Lesenswert ist ein Review von Li aus dem Jahr 2022: Li, Q. et. al. (2022). Effects of forest environment on health promotion an disease prevention- the Establishment of "Forest Medicine". Environ Health Prev. Med, 27:43.

"It has been reported that Forest bathing/Shinrin-yoku has the following beneficial effects on human health:

1. Shinrin-yoku increases human natural killer (NK) activity, the number of NK cells, and the intracellular levels of anti-cancer proteins, suggesting a preventive effect on cancers.
2. Shinrin-yoku reduces blood pressure and heart rate showing preventive effect on hypertension and heart diseases.
3. Shinrin-yoku reduces stress hormones, such as urinary adrenaline and noradrenaline and salivary/serum cortisol contributing to stress management.
4. Shinrin-yoku increases the activity of parasympathetic nerves and reduces the activity of sympathetic nerves to stabilize the balance of autonomic nervous system.
5. Shinrin-yoku improve sleep.
6. Shinrin-yoku increases the levels of serum adiponectin and dehydroepiandrosterone sulfate.
7. In the Profile of Mood States (POMS) test, Shinrin-yoku reduces the scores for anxiety, depression, anger, fatigue, and confusion, and increases the score for vigor, showing preventive effects on depression.
8. Shinrin-yoku may apply to rehabilitation medicine
9. Shinrin-yoku in city parks also has benefits on human health.
10. Shinrin-yoku may have preventive effect on COVID-19 by boosting immune function and by reducing mental stress.

Taken together, these findings suggest that Shinrin-yoku may have potential preventive effects."

Fazit: Ein kontemplativer Waldspaziergang hie & da erfrischt den Körper und befreit den Kopf. Let's do it!