I use negative reinforcement on myself. I've rigged up an electric shock zapper which I shock my
with everytime I go to eat something that isn't part of breakfast, lunch, or dinner.
I gave up on Ho-ho's really fast.
But you really really have to have the self-discipline to shock yourself when you want to cheat though. Otherwise it won't work. I'd use a taser, but they cost too much, and I tend to be less productive at work after I've stunned my junk three or four times.
I've lost 70 pounds this way - although I wasn't really overweight to begin with. I just wanted to give myself an eating disorder.