We’ve been hearing more and more about loneliness, and the “loneliness epidemic,” in recent years, as research has stared to lay out both its causes and effects. There are likely many reasons for this increasing psychological/societal issue, but one that’s almost certainly involved is our dependence on screens, and in particular social media. And a new study from the University of Pittsburgh and West Virginia University finds that social media use—or at least negative experiences on social—is linked to more feelings of social isolation, a.k.a. loneliness. (And below is a worthwhile infographic on loneliness.)

The team had previously reported that in college students, negative social media experiences were linked to depression: for every 10% rise in negative social media interactions a person experienced, their risk of depression rose significantly—by 20%. Positive experiences didn’t have any real effect. The authors suggested that the discrepancy exists because of the negativity bias, our tendency to remember and be affected by negative events much more strongly than positive ones. As always, it’s likely that the connection goes both ways: that in addition to social media leading to depressive symptoms, people who are already depressed may be more likely to use social media, or have negative experiences with it.

And the new study was very similar. The team queried undergraduates about their social media use, the types of experiences they had with it, and their mental health—in this study, of course, feelings of social isolation were of interest. The two variables were connected in a dose-dependent way: For every 10% rise in negative experience on social media, there was a 13% increase in loneliness. For positive experiences, there was no such connection.

Again, the authors suggest that it’s a two-way street—negative social media interactions may make one more likely to isolate, and that existing feelings of isolation could also lead a person to use social media more (and/or perceive more negative experiences on it).

“There is a tendency for people to give greater weight to negative experiences and traits compared with positive ones, and this may be particularly relevant when it comes to social media,” said study author Jaime Sidani in a news release. “So, positive experiences on social media may be associated with fleeting positive reinforcement, while negative experiences — such as public social media arguments — may rapidly escalate and leave a lasting, potentially traumatic impression. It also may be that socially isolated people lean toward social media use that involves negative interactions. It is probably a mix of both.”

Social media use, and closely related screen addiction in general, is probably just one of the many reasons people are feeling more isolated these days—our modern lifestyles, at least in certain countries, don’t exactly lend themselves to maintaining a meaningful social life. Variables like living by oneself, far from family and friends, aging alone, a lack of meaningful community, among others, are probably other significant contributors to the loneliness epidemic.

Below is an interesting infographic from Happify.com, which outlines some of the health and mental health effects of loneliness. The point isn’t to scare people about the fallout of being lonely, but just to get people thinking about the importance of social connection—and the reality that we should really work to make it a habit. (There are also tips on how to do this.) Just like eating well, exercising, and getting enough sleep, social connection is a lifestyle variable that we should see not as expendable, but as a non-negotiable.