A systematic review of the effects of mindfulness interventions on cortisol.

Cortisol is increasingly included in examinations of mindfulness intervention effects as an indicator of efficacy; however, the association of cortisol and mindfulness has yet to be rigorously evaluated. A systematic review of six studies examining mindfulness intervention effects on cortisol was conducted. Inconsistent results were found for mindfulness effects on cortisol. Significant changes in cortisol levels were observed in within-participants studies but not observed in randomised controlled trial designs. Mindfulness may influence cortisol, but findings are inconclusive. Mindfulness pathways and methodological differences influence variations in mindfulness effects. Robust protocols are needed to adequately examine mindfulness effects on cortisol.