Why is thin generally considered more attractive then fat?

Socieaty hollywood magazine all want people to fit in a box if you dont your fucked been there doen that im up to 183 and in my class its all i hear putitng on a few huh taking a nursing class every one will judge you but none of them are taller than me aso f them what i got more legs then alllll of em so fuck them!!!!!!!!!!!!!!!!!!!!!!!!!