Participants who practiced loving kindness meditation daily for seven weeks experienced a significant increase in daily positive emotions such as contentment, joy, gratitude, hope, and love. Those people also reported greater life satisfaction and lower depressive symptoms than before they started the meditation practice.
REFERENCE
Fredrickson BL, Cohn MA, Coffey KA, Pek J, Finkel SM. Open hearts build lives: positive emotions, induced through loving-kindness meditation, build consequential personal resources. J Pers Soc Psychol. 2008 Nov;95(5):1045-1062. doi: 10.1037/a0013262. PubMed PMID: 18954193; PubMed Central PMCID: PMC3156028.