A German research study, which surveyed nearly 600 Facebook users, found that participation in Facebook and other social networks can cause negative feelings and reduce members' satisfaction with their lives.
Over one-third of respondents reported mostly negative feelings. Additionally, almost 20 percent of recent online and offline events that produced envy took place on Facebook.
Envy may also cause users to embellish their own lives, which then sparks envy in others, leading to what researchers call an "envy spiral."
Passive social networkers, who only use the sites as a source of information, are most at risk for these negative feelings.