well i think weed speeds up the metabolic process and that is why you get hungry all of a sudden...i never am hungry though. its just that food looks so good and is extremely tempting and a box of cheezits is like meeting God while stoned. also once you start you cant quit until you fall asleep. water is good for you though. so i think if you smoke and then dont give in to the munchies, and excersize three times a week for 20 min. each time, you will start droppin the pounds.