Contagion gets a pretty bad rap, doesn’t it? After all, it’s not very often you hear about something being contagious and think, “I might have me some of that.” But the mere fact that something is highly communicable doesn’t mean it’s necessarily bad.
Case in point: a new study has used the kind of modelling usually reserved for tracking the spread of infectious diseases to see how the mood of teenagers spreads among their social networks. Researchers at the University of Warwick in the UK analysed data from a study of more than 2,000 US high school students to see how teens’ moods affect one another. Their conclusion? Happiness is contagious, while – fortunately – depression isn’t.
“Depression is a major public health concern worldwide,” said Frances Griffiths, head of social science and systems in health at Warwick Medical School, in a statement. “But the good news is we’ve found that a healthy mood amongst friends is linked with a significantly reduced risk of developing, and increased chance of recovering from, depression.”
Individuals in the study were classified as having either low mood (depressive symptoms) or healthy mood (no depression) according to traditional clinical indicators of the disease. Both moods were then tracked using a contagion model to see if and how the moods were transmitted between a large adolescent population.
The results, published in Proceedings of the Royal Society B, offer some promising insights into how we might combat depression amongst teenagers. According to the research, adolescents with five or more mentally healthy friends have half the probability of developing depression when compared with teens who have no mentally healthy friends.
Plus, having 10 healthy friends gives adolescents double the probability of recovering from depressive symptoms, compared with teens with only three healthy friends.
Given that happiness transmits among teens but depressive symptoms don’t, the researchers say the burden of depression among adolescents can be combated through low-risk and low-cost social intervention programs.
“Our results suggest that promotion of any friendship between adolescents can reduce depression since having depressed friends does not put them at risk, but having healthy friends is both protective and curative,” said Edward Hill, lead author of the study.
While the results might seem kind of obvious in hindsight – having friends around makes us less unhappy, in essence – any scientific proof that can help us understand how to make young people feel better about themselves has to be welcomed wholeheartedly.
“As a society, if we enable friendships to develop among adolescents (for example providing youth clubs) each adolescent is more likely to have enough friends with healthy mood to have a protective effect,” said Thomas House, co-author. “This would reduce the prevalence of depression.”