Background: Studies on Complementary and Alternative Medicine (CAM) have been forming a significant body of evidence, but not without limitations. While most studies reported benefits, some of them reported mixed effects or inconclusive results. Objectives: This study investigates the short-term effects of CAM interventions on depression, anxiety, and stress scale (DASS). Furthermore, the research explored the underlying mechanisms linking interventions to observed effects. Study Design: A longitudinal pilot study was conducted, in which participants engaged in CAM-based interventions including Lian Gong, Forest bathing, Music therapy, Circle dancing, and Hatha-yoga. The Depression, Anxiety, and Stress Scale (DASS) was used to assess mental health before and after interventions. Methods: A total of 149 repeated measures were collected. Statistical analyses included paired comparisons using one-tailed tests (Student t-test or Wilcoxon test) based on the distribution of data. Effect sizes were calculated following established guidelines. A significance level of 0.05 and a test power of 0.8 were maintained. Results: The study demonstrated promising short-term reductions in DASS scores across different CAM interventions. Hatha-yoga notably reduced depression and stress with medium effect sizes. Lian Gong, Forest bathing, Circle dance, and Music therapy also showed significant reductions in these disorders, with varying effect sizes. Conclusions: This pilot study provides evidence of the positive impact of CAM on mental health, although effectiveness varies by intervention type. Hatha-yoga, Lian Gong, Forest bathing, Circle dance, and Music therapy all exhibited potential benefits. These findings underscore the importance of further research, including long-term longitudinal evaluations, to explore sustained effects and temporal variations over time.