I'm also far from overweight and I've got stretch marks all over my hips. Its hereditary, some people get it, some don't. Those with taut skin that are not overweight can get them even if they gain just a little weight (that's my case). You can't avoid stretch marks with ANY moisterizer, or anything you put on your skin (except possibly retin-A (but it only diminises them 20-30%). The tear is in the deepest part of the dermis; the skin is ripped from the inside out. Most GG's have stretch marks, ask them. Most of them fade over time and become barely noticeable. Try to keep your weight down, even lose a bit of weight, so you've got a bit of looseness in your skin (besides that, nothing really helps).