I believe that a big portion of why people comment negatively about their body is due to how they believe others will perceive them based on what others look like. We see seemingly perfect women and men plastered across billboards and on TV screens in front of us, and then any little flaw we see when we look in the mirror becomes a big deal in comparison to those airbrushed ads. We go and hang out with our friends and know that they have seen these "perfect people" in the media and we think to ourselves that we don't amount to them so we jokingly comment on our perceived flaws. It's almost like we think others will voice our flaws if we don't, so saying them on our own makes us feel better because then we can assure our peers won't be secretly thinking about them. But that's just wrong.
If it's about thinking you won't have friends if you're not stereotypically beautiful, or if it's about not being able to find a boyfriend or girlfriend because you think they'll see you as ugly, then it's truly an issue of psychological nature.
On the other hand, if it's others that tell you you're not beautiful then it doesn't actually have anything to do with you at all, it's an issue that the other person has to deal with. It may hurt to hear those negative comments, but you can't let it lower your self-esteem. You just have to remind yourself that it's the other person who has an issue if they think it's okay to say those things to you.
The beauty in our world is uniqueness. Yes people say it's all about being beautiful on the inside, but let's face it, beauty on the outside is a factor and we all know that. However, it's about the fact that beauty on the outside is not measured by stereotypic beauty portrayed in the media, it's about beauty found within uniqueness.
You don't have to completely prevent yourself from thinking negative thoughts about your body. It's about being able to recognize what you are thinking, and to actively let the thought go. After the thought passes it's important to concentrate on more positive thoughts. Work on accepting your body without making comparisons.
We are overly critical of our own bodies mostly due to what we believe we are perceived as. But most of the time others don't see what we see when we're standing up close and over analyzing ourselves in a mirror.
In the end, everyone is beautiful in their own unique way, and it's one thing for me to say that, but it's important that everyone out there is able to say it about themselves. Let's work together on appreciating not only our own body but also everyone else around us. Let's not jokingly say we hate things about ourselves, because it's important to remember that it really isn't a joke in the end.
I believe it's important for us to eliminate this saying from our vocabulary...and in the process learn to enjoy fuelling your body with nutritious (and delicious) foods, and getting some exercise with friends and family.
Learn to love yourself and those around you, on the inside and out.