More than a billion people log on to Facebook every day. Over on Instagram, users endorse each other’s photos with 3.5 billion daily “likes.” And in the course of 24 hours, Snapchat users gobble up 7 billion videos on their smartphones.

Now psychologists are starting to look at how all that checking in is taking a toll on how we sleep and feel.

In a new study, researchers at the University of Pittsburgh asked 1,788 young adults ages 19 to 32 how often they use 11 of the most popular social networks including Facebook, Instagram, Vine, YouTube, Snapchat, Twitter, and LinkedIn. And they found that almost half of those surveyed said they averaged more than four daily check-ins on social media.

But there could be a darker side to obsessively checking your network when it comes to getting a good night’s sleep. The researchers found the most addicted social media consumers, those who clicked on their networks more than 58 times a week (that’s an average of about nine visits per day) were three times more likely to report disturbed sleep than those who only checked in roughly once a day.

Lead study author Jessica Levenson says surprisingly, the repeat clicks were more closely related to sleep disturbances than how much total time users spent on their social networks. “If this finding continues to come out, this kind of checking behavior is a good target for intervention,” she says.

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But self-help interventions, like trying to keep tabs less frequently throughout the day, won’t come easy to social media buffs according to behavioral economist Dan Ariely. He says this constant checking in is hard-wired. Ariely says it’s unlikely that we’ll be able to follow any rules we make for ourselves when it comes to restricting how often we glance at social media.

He explains the draw to Facebook like this:

“We can find out at any moment that we missed a wonderful thing, and we are worried that we are going to miss it and we’ll find out,” Ariely says. “We keep on checking and checking and checking so we don’t feel that.”

This is the feeling of regret at work. Some might call the feeling “FOMO,” also known as “fear of missing out” on the best of what’s happening. And while the new evidence from the Pittsburgh researchers suggests this FOMO phenomenon could also be preventing people from getting a good night’s sleep, they say more research is needed to pinpoint the exact cause of the disturbed sleep.

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The research comes just as our latest findings about Fortune 500 CEOs suggest they are still largely reluctant to join the ranks of the social media savvy. But with so many of their own sleep schedules rumored to be in the neighborhood of four hours a night, their slow adoption of social media… still doesn’t mean they’re gaining much when it comes to Zzz’s.