I saw a program about this on the Discovery channel once. It was about why we consider certain body images beautiful. They said it comes from our evolutionary background. Men who are fit give us the impression of being good providers. Women who are fit (especially those with big breasts) give the impression of being able to care for young. That is the technical reason why people judge by body image, but lets remember one thing. It is precisely because we are evolved beings that we shouldn't judge. Because we also understand emotion and empathy. We have so much technology now that people of all types can provide and care for others. At this point in history, being judgmental is nothing but a character flaw.
Idk:/ my dad is VERY judgemental of body imagine, and it makes me self-conscious sometimes. Think it's part of what triggered my eating disorder at 14... Beauty comes in all shapes and sizes, and it's so unfair of us to think that there is some set definition to beauty... It's what makes you different that makes you beautiful.