The effect of loving-kindness meditation on positive emotions: a meta-analytic review

Loving-kindness meditation (LKM) effectively enhances positive emotions, according to a systematic review and meta-analysis of 24 empirical studies involving 1,759 participants. The analysis found medium effect sizes for LKM interventions on daily positive emotions in both wait-list controlled randomized trials and non-randomized studies, and small to large effect sizes for immediate positive emotions from ongoing practice. Interventions focused specifically on loving-kindness produced medium effects, while compassion-focused interventions yielded small effects. The length of interventions and meditation time did not influence outcomes, but studies without didactic components showed small effects. Individual differences and the nature of positive emotions also affected results. More research is needed to identify active intervention components and applicability in clinical populations.

Study at a glance

Abstract

While it has been suggested that loving-kindness meditation (LKM) is an effective practice for promoting positive emotions, the empirical evidence in the literature remains unclear. Here, we provide a systematic review of 24 empirical studies (N = 1759) on LKM with self-reported positive emotions. The effect of LKM on positive emotions was estimated with meta-analysis, and the influence of variations across LKM interventions was further explored with subgroup analysis and meta-regression. The meta-analysis showed that (1) medium effect sizes for LKM interventions on daily positive emotions in both wait-list controlled RCTs and non-RCT studies; and (2) small to large effect sizes for the on-going practice of LKM on immediate positive emotions across different comparisons. Further analysis showed that (1) interventions focused on loving-kindness had medium effect size, but interventions focused on compassion showed small effect sizes; (2) the length of interventions and the time spent on meditation did not influence the effect sizes, but the studies without didactic components in interventions had small effect sizes. A few individual studies reported that the nature of positive emotions and individual differences also influenced the results. In sum, LKM practice and interventions are effective in enhancing positive emotions, but more studies are needed to identify the active components of the interventions, to compare different psychological operations, and to explore the applicability in clinical populations.