Looking at too many photos of your high school friend’s cute babies and homemade gourmet dinners may build feelings of envy and extreme sadness, university researchers say.

Researchers at Nanyang Technological University, Bradley University and the University of Missouri Columbia recently surveyed 736 college students and found that, “basically, if you quietly stalk your friends on Facebook and then realize that your life doesn’t measure up to theirs, you feel bad about yourself,” Fox 4 reports.

“Facebook can be a fun and healthy activity if users take advantage of the site to stay connected with family and old friends and to share interesting and important aspects of their lives,” Margaret Duffy, a professor at the University of Missouri School of Journalism, says in a news release.

“If Facebook is used to see how well an acquaintance is doing financially or how happy an old friend is in his relationship — things that cause envy among users — use of the site can lead to feelings of depression.”

The researchers say their findings apply to the “surveillance use” some users engage in to see what their old friends are doing today.

Facebook postings about “expensive vacations, new houses or cars, or happy relationships” can spur feelings of envy among surveillance users.

“We found that if Facebook users experience envy of the activities and lifestyles of their friends on Facebook, they are much more likely to report feelings of depression,” according to Duffy.

“Facebook can be a very positive resource for many people, but if it is used as a way to size up one’s own accomplishments against others, it can have a negative effect. It is important for Facebook users to be aware of these risks so they can avoid this kind of behavior when using Facebook.”

The researchers urge Facebook users to improve their “social media literacy.”

“Based on our study, as well as on what others have previously found, using Facebook can exert positive effects on well-being. But when it triggers envy among users, that’s a different story. Users should be self-aware that positive self-presentation is an important motivation in using social media, so it is to be expected that many users would only post positive things about themselves. This self-awareness, hopefully, can lessen feelings of envy,” says researcher Edson Tandoc.