The answer is mindfulness.
To see why, we need to look back to what caused this question to arise in the first place. Surely, the overeating caused some suffering and some wisdom could see that overall, this is a negative thing and needs to stop.
But that was not the winning decision at the moment of eating. The desire to eat stepped up powerfully, obscuring the wisdom and was the winner at that moment. The Buddha taught about sensual experiences - (the noble disciple), sees the allure of it (assāda), the drawback (ādīnava) and the escape from it (nissaraṇa)...
The reason wisdom did not win the battle at the moment of action is that the drawback was not fully understood (except intellectually). With continuous mindfulness, the causes and effects are seen...again and again. Seeing how, not wanting to fall, one falls into the trap anyway... When the allure, drawback and escape are seen, no techniques or restraint are needed, the desire falls away on its own.
This takes many instances, so need not to be harsh on oneself in the meantime. Just keep...observing the arising of the desire, the wisdom fighting that...and then either the wisdom wins in that instance and mindfulness then recognizes the ease that results...or the desire wins and mindfulness recognizes the drawbacks as they take shape...
Again and again....only two ingredients required -
- mindfulness and
- The wisdom gained so far