The spread of happiness

Happiness is contagious. Like a virus or a yawn, happiness can spread to your friends and your friend’s friends – in fact to your actual social network (the real-life one, not the social media one) up to three degrees of separation.

That’s what a powerful study following 4,739 individuals over 20 years concluded and reported in the British Medical Journal (BMJ). The authors not only interviewed and tested these individuals, but also their parents, siblings, children, spouses, and at least one friend every two to four years during that 20-year period. Home and work addresses allowed the determination of neighbour relationships and co-working ties within everyone’s network. Questions asked to the participants measured how often they agree with statements such as “I felt hopeful about the future” and “I enjoyed life”.

According to the study, a person is, on average, 15.3% more likely to be happy if a person related to her (spouse, sibling, friend…) is happy. This percentage reduces to 9.8% if a second-degree connection (such as a friend of a friend) is happy, and down to 5.6% for the third degree of separation – an effect that was nonetheless still significant. The main figure produced by the authors of the study and available on this link shows clusters of happy people (yellow dots) and sad people (blue dots), with in-between individuals in green. People at the core of their social network are more likely to be happy than the people at the periphery, meaning that the more you are surrounded by happy people, the more happy you are likely to be.

Moreover, happiness in coworkers has no significant effect on oneself, but friends or neighbours that live in close proximity can really increase your level of happiness. For instance, one will see his chances of becoming happier by 42% if a friend (or sibling or parent, etc…) living in an area of less than 0.8 km is becoming happy. This effect can last for one year. The other good news is that happy friends have more influence on your own happiness level than unhappy friends.

Since the follow-up of participants ended in 2003, the impact of social media such as Facebook and Twitter was not included in the study. Recent research on this topic is somewhat contradictory, although often demonstrating that virtual connectivity is rather decreasing well-being through social comparison, especially in lonely people. Long-term studies with more hindsight are required to truly understand the effect of social media on happiness.

In a world where individuality prevails and social connections are becoming increasingly dependent on a screen, the study reported here is there to remind us that humans are social animals, and interpersonal ties are fundamental to its well-being. Trust in people, friendly contacts with the neighbours and engagement in the community can create a wave of happiness that could ripple to your friend’s friend’s friends.

Fowler, J.H. and Christakis N.A. Dynamic spread of happiness in a large social network: longitudinal analysis over 20 years in the Framingham Heart Study. BMJ 2008, 337:a2338
De Vries, D.A. and Kühne, R. Facebook and self-perception: Individual susceptibility to negative social comparison on Facebook. Personality and Individual Differences, 2015, Vol. 86, pp. 217-221
Arampatzi, E., Burger, M.J. and Novik, N. Social network sites, individual social capital and happiness. Journal of Happiness Studies, 20 October 2016

Credit photos:
Featured image by Vilandrra via Pixabay (Creative commons CC0)


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