I have/had the same problem. I'm working on it now. Usually, it was because I was either addicted to the sugar and salt (let me guess - you're not exactly shoveling down veggies) or I was eating my emotions, so to speak. Before you eat, stop for a minute and ask yourself WHY you want to eat. If you're full but you just want it to taste good, you need a detox. And no, that doesn't mean some kind of creepy juice diet or something. Just stay away from junk for a week. It gets easier after that!

If you realize you're eating because you're bored or angry or sad, ask yourself this: "Will eating this box of cookies make me feel better about my situation?" The answer is no. "How will I feel after eating this?" Well, your problem, whatever it is, will still be there, and on top of that, you'll feel sick to your stomach and you'll regret all of that shitty food you just put into your body for no reason.

Work on the roots of the problem, and good luck.

Try allowing yourself to eat smaller meals a day, this way your sugar levels will maintain throughout, and you won't feel a crazy craving or need to stuff yourself with more food than you would regularly eat if you ate regularly.