I'm never exercising my mom says I put on weight and I'm always eating yet I was told I have a body fat of 12.7 percent and muscle mass of 82.4 and I'm 99.4 lbs and 5'1" and that's in the morning Before I've had anything to eat. So why am I underfat? If I am of healthy weight? My bust is a healthy 32C. I'm skinny but I'm not very muscled nor am I bony. No one calls me bony considering my chest size how come it doesn't make me within healthy range what's wrong with me?