The Messenger of Allah (sal Allahu alaihi wa sallam) said: “The human does not fill any container that is worse than his stomach. It is sufficient for the son of Adam to eat what will support his back. If this is not possible, then a third for food, a third for drink, and a third for his breath.” [Jami at-Tirmidhi]
Eating and drinking is not the be all and end all of man’s life. The main purpose of our creation is to fulfill our oath of allegiance to Allah [Quran, Surah Al-A’raaf] and earn our place in Jannah. To do so a healthy body helps and a healthy body is maintained by keeping a part of our stomachs empty at meal times. We need to stop eating while we still feel a little hungry. To constantly keep eating till we feel satiated causes our stomachs to go bad. We would, therefore, be well advised to eat only as much as is necessary.