'Many groups in the last decade have been keen to establish a link between kindness and happiness, including the UK government. Offering kindness to others has been explored as a possible panacea for many of our social ills, ranging from social isolation to more serious mental and physical health conditions. Our review suggests that performing acts of kindness will not change your life, but might help nudge it in the right direction. We recommend further research is done to compare the effects of being kind to family and friends as opposed to strangers. This is an area about which we know surprisingly little at the moment.'