What’s the last thing you think of before you go to sleep at night and the first thing you think of when you wake up every morning? Probably your social media accounts. There’s no denying that social media has taken over (almost) everyone’s lives whether we like it or not. And, according to a new study done by American Journal of Epidemiology, the more you use Facebook, the more likely you are to be depressed.

In their study, researchers used three different groups of data taken from over 5,200 adults over a two-year time period. They looked at how often the subjects reported using Facebook to see if there was a connection between well-being and Facebook usage over time, defining well-being as being satisfied with life, high self-reported mental and physical health, and a healthy BMI. The measures of Facebook usage they observed were liking other people’s posts, creating your own posts and clicking on hyperlinks. Additionally, they analyzed each participants’ IRL social networks—each respondent had to name a maximum of four friends they talk to about important matters and four friends with whom they regularly hang out.

At the end of the study, the researchers found that, while social networks in the real world led to a more positive overall well-being, more Facebook usage had a negative effect on them—especially on their mental health. A majority of the measures of Facebook usage were associated with decreased mental health after one year.

“We found consistently that both liking others’ content and clicking links significantly predicted a subsequent reduction in self-reported physical health, mental health and life satisfaction,” reported Holly B. Shakya and Nicholas A. Christakis, the authors of the study.

While you’ll probably get depressed if you spend too much time social stalking, the researchers couldn’t explain exactly why. But the next time you wake up and automatically reach for your phone, maybe think twice before you click that little blue button.