I'm not sure why only teenage girls were studied (are they more prone to depression than boys, or do they just use social networking sites more?) but researchers at Stony Brook university have discovered that rather than a problem shared being a problem halved, too much chatting on Facebook and via text encourages teenage girls to become depressed, as they obsess over the same issues, "co-ruminating" on their love life disasters, school worries, family problems etc. New technology allows girls to talk to their friends whereas once they would have had to allow the outside world to distract them. The answer? Less Facebook, more face-time doing non-techie stuff, I guess.

Via CNET.