Forest bathing (Shinrin-yoku) shows potential to prevent depressive symptoms by modulating neuroendocrine-immune pathways

Depression affects over 280 million globally, posing a significant public health challenge with limited universally effective preventive strategies. Current pharmacotherapies often have side effects or limited efficacy for some individuals, driving interest in non-pharmacological interventions. Shinrin-yoku, or forest bathing, a Japanese practice of immersing oneself in forest environments, has emerged as a promising complementary approach, anecdotally linked to stress reduction, immune enhancement, and mood improvement. This review explores its potential to prevent depressive symptoms by examining underlying mechanistic pathways.

This narrative review systematically synthesized existing evidence on forest bathing's effects on depressive symptoms and its mechanisms. Researchers conducted a structured search across major scientific databases, identifying studies that investigated psychological responses, neuroendocrine and autonomic regulation, immune-inflammatory markers, and related physiological parameters. The review aimed to consolidate findings on how immersion in forest environments might influence mental health outcomes, particularly focusing on preventive potential.

Across diverse populations, forest bathing consistently demonstrated beneficial effects. Reviewed studies reported reduced negative mood states, improved vigor, and positive impacts on anxiety, depressive symptoms, and sleep quality. Stress biomarkers were also beneficially affected.

Mechanistically, forest bathing appears to modulate the psycho-neuro-endocrino-immune network. This modulation involves improved sleep, reduced stress hormone levels, and enhanced parasympathetic activation. Furthermore, the practice was associated with increases in circulating serotonin, oxytocin, and insulin-like growth factor-1 (IGF-1), alongside reduced inflammatory markers. These findings suggest a multi-faceted biological basis for the observed psychological benefits.