# A comprehensive evaluation of the health benefits of forest therapy for cancer survivors

## TL;DR

A study in Taiwan found that forest therapy significantly improved mood and reduced stress in cancer survivors, especially those with higher initial distress.

## Contribution

This is the first study to evaluate forest therapy for cancer survivors in Taiwan, showing its potential as a complementary intervention.

## Key findings

- Forest therapy led to significant improvements in mood, anxiety, depression, and cortisol levels among cancer survivors.
- Participants with higher baseline distress showed greater improvements, suggesting tailored interventions may be more effective.
- The study highlights the importance of considering demographic and emotional factors when implementing forest therapy programs.

## Abstract

While advancements in cancer treatment have improved survival rates, some survivors continue to experience emotional difficulties that adversely affect overall well-being. Forest therapy, a nature-based intervention, has demonstrated potential in alleviating psychological and physiological stress.

This single-arm pre–post study evaluated a two-hour guided forest therapy session in a submontane forest in Taiwan. Participants were recruited via posters and online registration forms disseminated by the Linsen Chinese Medicine and Kunming Branch (LCMKB) of Taipei City Hospital and were screened for eligibility according to predefined inclusion and exclusion criteria. Outcomes included psychological measures—the Profile of Mood States 2nd Edition–Adult Short (POMS 2-A), Beck Depression Inventory–Second Edition (BDI-II), and Beck Anxiety Inventory (BAI)—along with physiological indicators (heart rate, blood pressure, heart rate variability, salivary cortisol).

Of the 40 participants, 38 completed the program. Significant improvements were observed in mood disturbance (The Total Mood Disturbance of POMS 2-A: 4.0 → −8.0), anxiety (BAI: 5.0 → 3.5), depression (BDI-II: 5.5 → 4.0), and salivary cortisol levels (1.07 → 0.42 µg/dL), all with large effect sizes. Regression analyses suggested that baseline emotional status and certain demographic factors may have influenced outcomes. Participants with higher initial anxiety and depression, younger age, and shorter cancer duration appeared to show relatively greater improvements.

This first study of forest therapy among cancer survivors in Taiwan provides preliminary evidence that guided forest therapy may be a useful complementary approach for enhancing emotional well-being and reducing physiological stress. Significant improvements were observed across multiple psychological measures (POMS 2-A, BAI, BDI-II) and in salivary cortisol. Benefits were more pronounced among participants with higher baseline distress, younger age, or shorter cancer duration, underscoring the importance of considering baseline health profiles and demographic characteristics when designing interventions.

Approved by the Taipei City Hospital Research Ethics Committee (TCHIRB-11104010). ClinicalTrials.gov Identifier: NCT06001723.

The online version contains supplementary material available at https://doi.org/10.1265/ehpm.25-00333.