New research suggests that Facebook could adversely affect the mental health of its users.

Researchers at the university of Missouri-Columbia have found that Facebook use can lead to symptoms of depression if the social networking site triggers feelings of envy among its users.  This may have a lot to do with how Facebook users use the site.

"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," researcher Margaret Duffy said in a statement. "However, 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."

For the study, researchers surveyed young Facebook users and found that some of those who engage in "surveillance use" of Facebook also experience symptoms of depression while those who use the site simply to stay connected do not suffer negative effects.

Surveillance use of Facebook occurs when users browse the website to see how their friends are doing compared with their own lives. The researchers found that Facebook postings about things such as expensive vacations, new houses or cars, or happy relationships can evoke feelings of envy among surveillance users. They say that these feelings of envy can then lead to Facebook users experiencing symptoms of depression.

"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," Duffy said. "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."

Researchers said 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.

"The self-awareness, hopefully, can lessen feelings of envy," researcher Edson Tandoc said.

The findings are detailed in the journal Computers in Human Behavior.