In a recently published study, psychologists Christina Sagioglou and Tobias Greitemeyer of the University of Innsbruck report people "expect to feel better after using Facebook, whereas in fact, they feel worse."
Their evidence suggests it's not Internet browsing in general, but specifically social media use that brings people down. It also points to a likely reason: The nagging feeling that you've been wasting time.
"Our findings suggest that-on a daily basis-hundreds of millions of people engage in an activity that they consider (not very) meaningful," they write In the journal Computers in Human Behavior, "which in turn dampens their mood."
The first of their experiments featured 123 German-speaking Facebook users, who took a survey linked to on the social networking site. They first took a standard 20-item questionnaire that measures their current mood. They then were asked how much time they had spent on Facebook immediately before taking the survey.
The results: The more time they had spent on Facebook, the less positive their current mood.
Their second experiment featured 263 people recruited through Amazon's Mechanical Turk. One-third of them spent 20 minutes on Facebook. Another third spent 20 minutes browsing the Internet but avoiding social networking sites.
The final third went directly to the second part of the experiment, in which all participants took that same survey measuring their current mood. A final survey measured the extent to which they felt they had been doing something useful or meaningful during the previous 20 minutes.
Once again, those who had just been on Facebook reported less-positive moods than those in the other two groups. Further analysis found the Facebook users' scores were directly related to a feeling they had "wasted time on a meaningless activity."
The final experiment, featuring 101 active Facebook users, directly asked them to indicate whether they believed being on the site would make them feel better or worse than before they logged on. It found they overwhelmingly assumed - incorrectly - that Facebook would improve their moods.
So why do we keep returning to Facebook thinking it'll make us feel better, when it fact it does the opposite, at least in the short-term? The researchers can only guess at this point; They speculate that a strong, evolution-based drive for social contact may distort our memories of past experiences.
"Although Facebook is an excellent tool for… staying in touch with acquaintances," they conclude, "there are serious disadvantages of using it, such as envy, lowered life satisfaction of basic psychological needs, and dampened mood."
Of course, it's possible that social media usage may have long-term positive effects that counteract the short-term downward mood documented here. And of course different people use social media in different ways; If you're on Facebook promoting a cause, that's quite different from idly noting what your friends are up to.
But given the strong connection between our well-being and the pursuit of meaningful activities, it's hard to see how any medium that we largely equate with time-wasting could be a net positive. Perhaps Facebook isn't really our friend after all.