Symmetrical Global Mental Health (Sym-GMH): Ayahuasca and shipibo traditional medicine for lasting changes in personality and quality of life
Psychedelics April 20, 2026 José Carlos Bouso, Óscar Andión, Jordi Cantillo et al.
A 12-month study of 264 Western participants who attended Shipibo-led ayahuasca retreats in the Peruvian Amazon found lasting psychological improvements. Neuroticism and Openness to Experience decreased, while Extraversion increased. Quality of life improved across all measured domains, and decentering capacities increased with moderate to high effect sizes. Most participants (91.7%) reported long-term benefits, primarily in spiritual well-being, mental health, and personal growth. Adverse effects were minimal (2.3%). Higher baseline psychological distress was associated with higher Neuroticism and lower decentering, suggesting that enhancing decentering may serve as a resilience factor. The findings support ethical, non-extractive integration of traditional Amazonian practices into global mental health frameworks.