Happiness spreads among friends

New research led by the University of Warwick has suggested that having friends who suffer from depression does not increase your own chances of poor mental health.

In fact, the research indicated that having a healthy set of happy friends significantly reduces the chances of developing depression, and increases the chances of sufferers recovering from it.

The research is based on studies of over 2000 US teenagers at high school level. The academics used a mathematical model to monitor how the various groups influenced each other’s moods.

The spread of mood was tracked in a similar way to that of infectious disease, seeing how quickly a healthy or low mood can pass through a group of individuals, if at all.

Individuals were classed as either having depressive symptoms (low mood) or not being depressed (healthy mood), in the same vein as how clinicians diagnose the illness.

Our results offer implications for improving adolescent mood.”
Frances Griffiths

The research overall concluded that depression does not spread among friends, but it does work the other way: having enough friends with a healthy mood can halve the probability of developing – or double the probability of recovering from – depression over a six to 12 month period.

The suggestion is that adolescents who have five or more mentally healthy friends are half as likely to become depressed than if they had no healthy friends.

Meanwhile, teenagers who have 10 healthy friends have double the probability of recovering from depressive symptoms compared to adolescents with just three healthy friends.

A second-year English Literature student who is currently undergoing treatment for depression, but who wished to remain anonymous, commented: “People always say how important it is to surround yourself with happy and supportive friends, and this research certainly backs up this opinion.”

“While I personally still suffer from depression despite having a large group of mentally healthy friends, I imagine my mental health would be far worse if I didn’t have them, or the support and happiness they bring me, at all.”

Professor Frances Griffiths, head of social science and systems in health at Warwick Medical School, stated: “Depression is a major public health concern worldwide.”

He went on to say: “In particular [our results] suggest the hypothesis that encouraging friendship networks between adolescents could reduce both the incidence and prevalence of depression among teenagers.”