Remove yourself from the temptation! Drink water, or eat something healthy, like fruit or something. Another thing that I usually ask myself is "Am I REALLY hungry, or just want it because it's there" feeling? I get those alot! It usually passes after awhile. Also I'm an emotional eater, and when I'm stressed and such, I tend to crave "comfort foods"....
I agree with Jasmine, if you eat bad in the morning...it's harder to get back on track for the rest of the day.
"You can have anything you want--if you want it badly enough. You can be anything you want to be, do anything you set out to accomplish if you hold to that desire with singleness of purpose." ~ William Adams