Facebook Can Put You In a Bad Mood: How Negativity on Social Networks Is Contagious

If you're scrolling through your Facebook feed and you suddenly feel your mood plummeting, take a minute to consider what your friends are posting about. According to recent analysis of Facebook data, negative social media posts have a domino effect, increasing the likelihood of a bad mood in anyone who reads them. Thankfully, the opposite can be said about positive posts: see an upbeat update, and you're more likely to feel like smiling yourself.

Researchers analyzed over a billion updates from a million or so Facebook users from January 2009 to March 2012. The anonymous English updates were put through a computer program that calculated their emotional content.

To test the impact of negative emotion, researchers looked at how a post from someone in a city hit by rain (more likely to be moody) influenced a friend in another, sunnier city. According to Fowler, professor of medical genetics and political science at the University of California in San Diego, the negative posts triggered an extra 1.29 more downbeat posts than normal among people's friends.

"People are not just choosing other people like themselves to associate with, but are actually causing their friends' emotional expressions to change," Fowler told the Guardian . So our moods spreads online, like they do in real life — no big surprise there. The jury is still out on whether the posed selfies, cheery updates, and carefully curated profiles of the Facebook-obsessed actually lead to contagious happiness or just intense social media exasperation.