First: Whatever aspect of your body you are declaring to be ugly, YOU ARE NOT THE ONLY PERSON WITH A BODY LIKE THAT. Other people whose bodies possess the same trait you are complaining about in your body are in all probability reading your entry in which you declare their body type to be ugly. The fact that you belong to a particular group does not make it acceptable to harass members of that group by calling them ugly.
Second: What exactly are you getting out of publicly humiliating yourself, anyway? Why do you have this compulsion to stand yourself in front of a group of other people and point at yourself and yell "You're so ugly!" at yourself in front of a watching audience? Would you ever be caught dead treating anyone else that way? Well, it doesn't make you look any less immature to me when you do that to yourself than when you do that to other people. Especially considering that, as I explained above, you are doing it to other people anyway, whether you acknowledge it to yourself or not. Unless the aspect of your body that you're complaining about is some freak mutation that's totally utterly unique in the entire history of humanity, such as eight-foot-long tentacles sprouting from the bottom of your torso in place of legs. But even then, you never know; someone somewhere might still have a mutation that vaguely resembles yours, and your insults aimed at your own body could still make them feel bad about theirs, too.
Here is are some examples of acceptable and unacceptable ways to initiate a discussion of your insecurities about your body:
Bad: "I can't stand how [insert body trait here] my body is! It's so ugly!"
Good: "[insert person or people here] said that [insert body trait here] is ugly, and that made me feel bad about my body."
Here are some examples of acceptable and unacceptable ways to react when other people assure you that your body is totally sexy, beautiful and amazing exactly the way it is:
Bad: I don't believe you! You're just saying that to try to make me feel better, and you didn't say it convincingly enough! I can read your mind and I know you don't really mean it! [Or any variation of this that doesn't quite outright say it, but heavily implies the same thing.]
Good: Thank you. [Optional:] That makes me feel a bit better.
If someone tries to make you feel better, it is very unkind for you to respond by tormenting them with continued false accusations that they must secretly think you are ugly, and by making them feel that they have to spend the rest of their day looking up new synonyms of "beautiful" in a thesaurus to be able to clear themselves of your false accusations. The polite response is to thank them. It is not necessary for you to claim that they have permanently alleviated all your insecurities about your body for the entire rest of your life and you will never feel bad about your body ever again. This is unlikely to be true. But if the person was of some help to you, it would be nice for you tell them that they helped; and even if you don't feel better at all, it would be nice for you to simply thank them for their effort and refrain from dragging the conversation on for the next hour and pointing out to them the entire extent to which their brief comments have unfortunately failed to solve every insecurity you've ever had. If you focus people's attention on whatever little their efforts did succeed in doing for you, not on what their efforts didn't succeed in doing for you, people are far more likely to enjoy interacting with you, and far less likely to end up feeling that they just completely exhausted themselves pouring every bit of energy they could spare into a futile attempt to make you feel better that ended up accomplishing nowhere near enough to justify making such an effort ever again.
And here's an excuse I'm tired of hearing: First a person posts something like, "I desperately need to get rid of all this disgusting ugly fat on my body!" Then when someone asks them to stop insulting fat people, the person replies, "I was just complaining about my health!" No, you weren't. The words "disgusting" and "ugly" have nothing whatsoever to do with health. If you were merely concerned about your health, your post would be concerned exclusively with, say, foot pain, or some other health issue that might conceivably be improved by weighing less. (Though speaking as someone with more than my share of foot pain, I suspect that arch supports or other shoe inserts may really be what you need.) There is absolutely no health-related justification for using words like "disgusting" or "ugly." Please dispense with the ridiculous pretense that there's any connection.
And tell me: Do you ever say to yourself, "Wow, I wish someone on my friends list would hurry up and write about how much they hate their body for being [insert body trait here]! I just love reading entries like that! I can't wait for the next installment about how much more miserable [insert person here] becomes each new time s/he looks into a mirror!"?
Do you? Because I really doubt that very many people ever look forward to those kind of posts at all. I certainly don't. I'd sooner read daily word-for-word transcriptions of every homework assignment or paid-work document you ever write all year round, or detailed descriptions of your every bowel movement. I'd sooner read a daily count of how many breaths you took per minute all 1,440 minutes of each day. I'd sooner listen to 8-hour-long phone posts that consist of nothing but recordings of how much you snored in your sleep each night. I'd sooner read practically anything than be subjected to continual details about how ugly you think you are.
Yet I am in the unfortunate position of really, really liking an awful lot of other things about quite a few people who write endlessly about how ugly they think they are. As a result, I really am not ever going to remove certain people who are guilty of this from my LiveJournal friends list, no matter how much they continue to inflict these posts on me. However, if you are one of those people, I think you should know: The poisons of your self-hatred are polluting my emotional airspace. Trying to read my friends page and coming across entries in which you claim you are ugly is like trying to walk down the street and having a giant truck drive by that spews out a gigantic cloud of carbon monoxide that leaves me unable to breathe properly for the next five minutes, and with a lingering sensation that my risk of eventually developing lung cancer just significantly increased. It makes my life significantly less pleasant than it would otherwise be.
What would be nice would be if all such people who are going to go right on writing endless journal entries about how ugly they think they are would just, say, create an opt-in or opt-out filter for such entries, so that I wouldn't have to see those entries or choke on all the carbon monoxide. Perhaps the filter could be called "People Who Don't At All Mind Hearing About How Ugly I Think Various Body Types Are, Which May Well Include Their Body or Their Future Body or Their Dearly Beloved Friends' Bodies." But somehow, I suspect that if people did that, they would not find very many people who would want to be included on such a filter.
While I'm on the subject, I do actually have something nice to say, too. I would like to personally thank keryx for consistently being the best emotional air purifier (at least for eliminating this particular form of emotional air pollution) that I have yet discovered on LiveJournal. If only more of the people who hate their bodies would read her journal, maybe fewer people would keep wallowing in hatred of their bodies all the time.