I suggest checking out T-Tapp.com.... I learned there something that helped understand why some people have the stomach bluge even if thin...and help get rid of it too
My roommate in college though in perfect physical shape had a "pooch" and it never went away. I didn't understand why all her sit-ups and watching her calorie intake didn't work it off. (we are both 5'11.)
Turns out she is a short torso... whereas I have a long torso. (Torso area.. top of hip to bottom of ribs) Meaning she has less space for all her internal organs than I do. Sit ups and dieting wouldn't get rid of her pooch

(however she has the most awesome legs ever!!!)
But there is a move I learned at T-Tapp called Organs in Place (OIP) and Half-Frogs (HF). It will help with the stomach area. Check it out with the link if you want.
It's listed under the Try Before You Buy section. So it's free to check out.
Best of luck to you!
Krista