How relivant is your weight to your body shape?

AmelieMustLoseWeight

When I was 15 I was 5'2 and 130 lbs. I went through puberty twice and my hips became large and my my shoulders became more broad and before I knew it I weighed 170 lbs. Im 21 now and strangely enough for 170 lbs I do not look it. Im wondering how much weight I really need to lose to look how I want to. I originally wanted to lose 50lbs to get back to my size when I was young. With my body shape I do not know if that is possible. I have a Marylyn Monroe kind of body. Low bust line and hourglass figure. With a large butt. Does anyone have a weird problem like this?