An overseas reader asked what I do with body-image issues. I wrote her this:
If it's full-blown dysmorphia, there's a chapter by DaLene Forester, "Image is Everything" in my book, EMDR Solutions 2, but if it's regular "I don't look like Twiggy, so I'm not okay" distress, I start with the 2-Hand Interweave: "In one hand, hold the way that society tells you that you should look. (body fat, shape, skin color, etc.) In the other, hold the body you have." 10 – 20 BLS. "What do you notice?"   
I then target with the EMDR standard protocol the shame, grief, anger, etc. that arises, taking special care with the cognitions. I often go back to the transmission of the messages: family, teasing, media images. "How did that message get into you?"  And go through the stages of grief in accepting the body they have.   Make sure you target shopping for clothes, being around people who have that ideal shape, and anyone who currently shames them for their shape. You may target them being naked (with a lover, at the gym, at the spa) and dealing with any distress that arises.
As a tall woman with no butt and a big belly (like every person on my dad's side), who got teased a lot as a teen,  I've gone through my own acceptance process. And it comes down to clearing the grief, accepting reality, and realizing that I'm lovable, that the person who matters thinks I'm sexy, and that this body is going to continue to deteriorate in the aging process, so I'd better take care of it.