I'd have to blame the cruelty of early adolescence (mainly grade school through highschool) for all the insecurities that I have about my body. I'd probably be less self-conscious of myself if no one made a big deal about my ears, my nose, my eyes, my chest, my butt, or my height. I find it easier to accept my body when others reinforce the notion that I'm not some freak of nature. If someone else thinks it's okay, it sort of counters whatever superficial criticism anyone else has to say about it; and I'm thankful that there are people who find me attractive, because as much as I'd hate to admit it, the opinions of others matter to me enough that I need it to feel reassured that there is nothing wrong with me.
I'm just glad that I'm no longer a teenager, heh.