Allah, out of mercy for His creation, ordered them to be moderate in their eating and drinking.
“…and eat and drink but waste not by extravagance, certainly He (Allâh) likes not Al-Musrifûn (squanderers).” [Al A`raf 31]
Also the Prophet (peace be upon him) advised his nation with moderation when he said:
“The son of Adam does not fill a vessel worse than his stomach. A few mouthfuls are sufficient for him in order to keep his back straight. And if he must fill his stomach; then one third for his food, one third for his drink and one third for his air.” [At-Tirmidhi]
To always eat to ones fill:
- leads to sicknesses of the body and soul.
- is a hindrance to ones worship of Allah and obedience to Him
- leads to laziness and sleep
From the hadith of the Prophet (peace be upon him) we know that there are three levels of eating:
- For a need (الحاجة)
- For sufficiency (الكفاية)
- In excess (الفضلة)
The third type – excessive eating – is disliked because it does not benefit the body but rather it harms it. It is like when you are carrying something heavy and trying to ascend upwards. It restricts the breathing and leads to other ailments such as:
- High blood pressure
- Arteriosclerosis (Hardening of the arteries)
- Strokes and heart attacks
When a person fills his stomach it applies pressure on the diaphragm which restricts the airflow and when the airflow is restricted it prevents the blood reaching many of the smaller blood vessels thus preventing the correct amount of oxygen reaching the body parts which in turn leads to many dangerous ailments.
This is a great principle from the principles of preserving health, a principle of the Prophet (peace be upon him).
This is a summarised portion from a lecture on prophetic medicine delivered by Shaikh, Dr Muhammad Musa Nasr.