The effects of yoga on positive mental health among healthy adults: A systematic review and meta-analysis

Objectives: The aim of this study was to present an overview of the research on the effects of yoga on positive mental health (PMH) among non-clinical adult populations. Methods: This was a systematic literature review and meta-analysis, including a risk of bias assessment. The electronic databases PubMed/Medline, Scopus, IndMED, and the Cochrane Library were searched from 1975 to 2015. Randomized controlled trials (RCTs) on the effects of yoga interventions on PMH among a healthy adult population were selected. Results: A total of 17 RCTs were included in the meta-analysis. Four indicators of PMH were found: psychological well-being, life satisfaction, social relationships, and mindfulness. A significant increase in psychological well-being in favor of yoga over no active control was found. Overall risk of bias was unclear due to incomplete reporting. Conclusions: The current body of research offers weak evidence that the practice of yoga contributes to an increase in PMH among adults from non-clinical populations in general. Yoga was found to contribute to a significant increase in psychological well-being when compared to no intervention but not compared to physical activity. For life satisfaction (emotional well-being), social relationships (social well-being), and mindfulness no significant effects for yoga were found over active or non-active controls. Due to the limited amount of studies, the heterogeneity of the intervention, and perhaps the way PMH is being measured, any definite conclusions on the effects of yoga on PMH cannot be drawn.