Why The obsession With bra size?

What I would like to know, is why there is this stupid obsession, by both es about a woman's size? This garbage has gone on for so long, and the obsession has become so great that the self image of our young women has been demoted to their bra size. They are so obsessed with it that they are damaging their bodies in order to be "popular" or whatever. Why can't we give these young girls and young women support for JUST WHO AND WHAT THEY ARE and not put such damaging pressure on how they are built?