As someone who is both very thin currently and has struggled with an eating disorder in the past, I have to disagree. While I have been bullied for being too thin, I don't think it's comparable at all to what fat people go through. My best friend is just slightly overweight and almost every time we go out for drinks she gets snide remarks and rude looks, if not worse. I just have to deal with people telling me to eat a burger every so often. Regardless, they're both pretty S●●●ty. I don't think it's ever necessary to comment on somebody's weight negatively, especially with the knowledge that physical disabilities and other health issues can have huge impacts on weight one way or the other.