Why dieting is difficult.....................

 When dopamine signaling reaches a certain level you increase learning dramatically to the point where something becomes habitual. We have a name for this: addiction. Addiction has a terrifying sound to it, but it’s just the point where something learned is so powerful it can overwhelm constructive behavior. . . .

Next time you’re “hungry”, ask yourself: “Would I eat broccoli?” If not, you’re probably not really hungry. This will make you a leaner person. No, I didn’t say happier. I said, “leaner.”

-More neuroscience on the subject here