A healthy mood is contagious, depression isn't

There’s another reason for us all to be more outgoing - a healthy mood is socially contagious whereas depression is not, new research has found.

A study by the universities of Warwick and Manchester, published in the journal Proceedings of the Royal Society B, has shown that having mentally healthy friends can help someone recover from depression, or even maintain mental health in the first place.

The researchers looked at over 2,000 adolescents in a network of students in the US and modelled the spread of mood using similar methods to those used to track the spread of diseases.

They found that depression does not spread, and having enough friends with a healthy mood can halve the probability of developing depression over a six- to 12-month period.

The researchers also found that this doubled the probability of recovering from depression.

In addition, having friends that are depressed does not make you more likely to also become depressed.

Applied Mathematician Edward Hill, at the University of Warwick, said:

We’ve ensured that the method we used was not confounded by homophily – that’s the tendency for people to be friends with others like themselves. This would have affected our research.

For example if many adolescents drink a lot of alcohol and their friends drink a lot too it may be that alcoholic drink cause depression among the young people rather than who they are friends with.

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