Well, usually you get stretch marks from weight GAIN, not from losing weight. Many people get stretch marks, from growing (taller!), from a change of body shape during puberty (I got some on my boobs, they are not visible any more), from pregnancy, hell even from weight lifting and muscle grow. I don't think having stetch marks is such a bad thing... A friend of mine got a baby 2 months ago, she's now only 8lbs heavier than before giving birth but her belly has stretch marks all over. I don't think she should feel bad about that!