there are a few people who have done research
specifically on the affect the media has on eating
disorders, including a pretty famous study that
the Harvard Center for Eating Disorders (I think that's the correct name)
undertook in Fiji, following the introduction
of TV there.
You should also consult the work
of Susan Bordo, Jean Killbourne and Jennifer
Schimmer (I think that's her name). And the
Renfrew Center, based in Philadelphia.