PRESPIRATION (COOLING SYSTEM IN HUMAN BODY)

In the Name of Allah, The Most Gracious, Most Merciful
Cooling system in human body, its components and function
The human body is divinely equipped with a marvelous cooling system, which some scientists call “Perspiration System”, which does the work of cooling, air-conditioning, and heat-control of the human body.
This system consists of 1,000,000 cooling units, i.e. sweat-glands. A sweat gland consists of a pipe 2 millimeters long and 1\10 millimeter in diameter. This pipe curls round itself and is linked with the skin. These pipes scatter equally all around the surface of the skin, but they are more numerous in such parts as the forehead, foot-sole, palm, and other parts of the body, with an average of 300 sweat-glands in each centimeter. Each sweat-gland is a complete cooling apparatus. If these million pipes were linked together, they would be 5 kilometers long.
In each 100 grams of the sweat produced by these cells there are 99 grams of water and one gram of solvents, half of which is salt and the second half is made up of uric acid and other chemicals. Every 24 hours, man produces from 600 to 1000 grams of sweat. And the process of perspiration is constant, but we do not feel sweat unless it is excessive. Skin softness and dampness are considered as evidence of the constancy of perspiration.
In other words, without perspiration the skin would not be soft or damp. Moreover, perspiration is considered as a safety valve for body temperature, just like the safety valve that protects pressure pots from exploding due to great internal pressure. This applies to the human body: if its temperature rose excessively, man would soon die. That is why there is a safety valve to control temperature of the human body. No sooner does internal body temperature rises than the sweat glands begin producing sweat that evaporates, absorbs the heat and causes the temperature to drop, keeping skin temperature within normal limits.
Among the great many functions of perspiration are: expulsion of uric acid, softening of skin, and control of body temperature.
Care should be taken to wash the body in order to remove unpleasant products of perspiration. This is because in our human body there are salts and uric acid, just as in urine. That is why it has been rightly said:
“Wash your body even if a Mudd (approx. one liter of water) costs a Dinar.”
In fact, Friday Major Ablution (i.e. washing of the whole body) in Islam is considered as a religious obligation in order to remove unpleasant products of perspiration; and it is Allah’s Right on a Muslim to wash his body once a week, as confirmed by the Messenger of Allah, (PBUH). Narrated Jabir that the Messenger of Allah, (PBUH), said:
“A Muslim has to perform Major Ablution (wash his whole body) every Friday.”
[narrated by Ahmad (14305) and Ibn Shaibah (5007)]
And cleanliness is the fruit of true faith, because washing of the whole body removes the bad unpleasant smell of perspiration and its unpleasant products after sweat has evaporated. It also opens pores of the skin and sweat-glands.
Praise be to Allah, the Lord of Creations