I think there are more people in
SL, especially among fashionistas, with eating disorders than people think. It would seem only natural for those who suffer from an eating disorder to make their avatars conform to their ideal. I feel sorry for those people, having suffered from an eating disorder myself. You never even realize how fucked up your expectations regarding ideal proportions are until you look at them from the outside, more so in a world where everyone already has a BMI of, what, 19?
Some people however just think having an anorexic-looking avatar is cool and some sort of fashion statement. Those people are morons and need to be smacked over the head with a copy of the DSM-IV.
And let me just say "fuck pro-ana." in lieu of ranting about this shit for a few pages.