● In relation to health and digestion, God’s Messenger recommended:
In eating, apportion a third of your stomach to food, another third to water, and leave the last third empty. The bowl most distasteful to God is a full stomach.24
In another similar hadith, God’s Messenger, upon him be peace and blessings, also says:
What I fear concerning my community is a large paunch, oversleep, idleness and the lack of certainty.25
All of the points mentioned in the hadith are each an antecedent to or result of the other. A man who spends an idle life of heedlessness with no self-control and self-criticism is apt to get a paunch, which, in turn, causes him to eat more and more. A full belly naturally causes excessive sleeping. Lastly, the one who is addicted to overeating and excessive sleeping will never be able to acquire certainty and deep conviction about the principles of faith. This is the case with most people in today’s world, a fact that provides another decisive proof of the Prophethod of Muhammad, upon him be peace and blessings.
● Another Tradition concerning health is as follows:
Treat your eyes with kohl, for it nourishes eyes and eyelashes.26
Many medical authorities state that kohl is useful for the nourishment of eyes and eyelashes.
Another substance, recommended by the Prophet, upon him be peace and blesings, and useful for health as an antibiotic and for its dermatological effect, is henna.27 Henna is better and more effective as an antiseptic and as a sterilizing agent than substances like tincture of iodine.