No Snacks, no sweets, no seconds. Except on Days that start with S. Too simple for you? Simple is why it works. Look here for questions, introductions, support, success stories.
You can't fail on an S-Day, so mark as success. But you're right, it isn't healthy, so you may not want to repeat that particular form of success again!
"Self-denial's a great sweetener of pleasure."
(Patrick McGoohan's "The Prisoner")