Meditation interventions efficiently reduce cortisol levels of at-risk samples: a meta-analysis

A meta-analysis of randomized controlled trials found that meditation interventions reduce cortisol levels, but the effect depends on the population. In 10 studies that measured cortisol in blood, there was a medium-sized significant reduction for at-risk groups—specifically patients with a somatic illness—but not for no-risk samples. In 21 studies using saliva samples, the overall effect was small and not significant, though a marginally significant reduction appeared for people living in stressful life situations. These results suggest meditation interventions are most beneficial for populations already at risk for elevated cortisol. Preliminary evidence indicates the benefits may persist over time.

Study at a glance

Abstract

ABSTRACT Previous meta-analytic results showed beneficial effects of meditation interventions for cortisol levels. In the present meta-analysis we tested whether effects are larger for those who might be in need of such stress reduction programs due to a risk for elevated cortisol levels as compared to no-risk samples. We included RCTs that measured change in cortisol levels. Based on 10 studies using blood samples meditation interventions had a significant, medium effect from pre-to post-test compared to the control group. Upon closer inspection, this effect was only present for at-risk samples, that is, patients with a somatic illness. In the 21 studies using saliva samples the effect was small and not significant, but there was a marginally significant effect for groups living in stressful life situations. This pattern may suggest that that meditation interventions are most beneficial for at-risk populations. These interventions might provide people with strategies of stress management that can contribute to well-being. Preliminary results suggest that benefits of meditation interventions might not fade with time.