The claim that 'helping makes you happy' has become a staple of pop psychology and self-help manuals. Performing 'random acts of kindness' has been touted as a sure-fire way of boosting your mood — doing good makes you feel good, as well as benefiting others. But do these claims stack up, or are they 'too good to be true'?

In order to find out, a team from the universities of Oxford and Bournemouth carried out a systematic review of the scientific literature. They analysed over 400 published papers that had investigated the relationship between kindness and happiness, and identified 21 studies that had explicitly put the claim to the test – that being kind to others makes us happier. They then conducted a meta-analysis, which statistically combines the results of these previous studies.

On this basis, they calculate that there is indeed an overall effect of kindness on happiness, but that the size of the effect is relatively modest — equivalent to less than one point on a 0-10 happiness scale.

They also find that lower quality studies tended to claim larger effects than the high quality research, which suggests that the true effect may be even smaller.

In addition, they note that existing research does not distinguish between kindness to family and friends versus strangers and, taking this into account, targeted kindness rather than indiscriminate kindness may have a greater effect on happiness.

Our review suggests that performing acts of kindness will not change your life, but might help nudge it in the right direction. Dr Oliver Scott Curry, Institute of Cognitive and Evolutionary Anthropology

Study lead author Dr Oliver Scott Curry, from the Institute of Cognitive and Evolutionary Anthropology at the University of Oxford, concludes: 'Humans are social animals. We are happy to help family, friends, colleagues, community members and even strangers under some conditions. This research suggests that people do indeed derive satisfaction from helping others. This is probably because we genuinely care about others' welfare, and because random acts of kindness are a good way of making new friends, and kick-starting supportive social relationships.'

He adds: '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.'

The study was commissioned by kindness.org, a new US-based, non-profit organisation which launched today, along with its digital platform. Funded by an anonymous donor, kindness.org commissions and publicises latest research into altruism, as well as promoting public action through its 'kindness initiatives' that encourage people to help one another.

Dr Curry is a Senior Researcher in the Institute of Cognitive and Evolutionary Anthropology, based in the School of Anthropology at the University of Oxford. He is also director of The Oxford Morals Projects, looking at the psychology of moral values, and how morality varies around the world.