2. Social networking sites lack privacy and expose users to government and corporate intrusions. 13 million users said they had not set or did not know about Facebook's privacy settings and 28% shared all or nearly all of their posts publicly. The US Justice Department intercepted 1,661 pieces of information from social networking sites and e-mails in 2011. The 2009 IRS training manual teaches agents to scan Facebook pages for information that might "assist in resolving a taxpayer case." 4.7 million Facebook users have "liked" a health condition or medical treatment page, information that is sometimes used by insurance companies to raise rates.
3. Students who are heavy social media users tend to have lower grades. Students who use social media had an average GPA of 3.06 while non-users had an average GPA of 3.82 and students who used social networking sites while studying scored 20% lower on tests. College students’ grades dropped 0.12 points for every 93 minutes above the average 106 minutes spent on Facebook per day. Two-thirds of teachers believe that social media does more to distract students than to help academically.
4. Social networking sites can lead to stress and offline relationship problems. A University of Edinburgh Business School study found the more Facebook friends a person has, the more stressful the person finds Facebook to use.