Hi. I'm 15 and when I was in elementary, my teacher told me that when women start losing weight their chest size decreases. I'm 140 and I want to be 120. If I lose those twenty pounds, will my breast get smaller or is that just a myth? Also, is it possible to lose about 20 pounds in 2-3 months with moderate exercising and dieting. Are there any standard charts that give the approximate weight for people of a certain height?