The fat cells shrink as they empty out giving that area of tissue more room inside it. Sad fact about fat cells, they never go away, they're always there, waiting to be filled in. There's a post somewhere on this site, perhaps Meg, who I think wrote it, can link it, about how the previously obese always test as obese on certain chemical testing, because we still have markers of the obese, our body chemistry is changed from that of an 'always normal weight person'. Fat cells can only be removed through surgery, which will help the appearance of the area. This is my understanding as a previous nursing student who changed majors cus those folks are crazy