Role of Water in Nutrition?

Water is one of the most precious gifts of nature. It is an essential and major component of all living things on earth. Water is one of the essential nutrients.


Author: Ranjeet Singh


Water is one of the most precious gifts of nature. It is an essential and major component of all living things on earth. Water is one of the essential nutrients. Thought not a food, it carries nutrients throughout the body in fact, it is more essential to human life than food; for a person may live for weeks without food but only for days without water.

The most important property of water is its versatility. It can be used effectively both inside and outside the body. It can be used in any form be it liquid, solid or steam. It can be used hot or cold or lukewarm, depending on the need.

Water is the largest constituent of human body. About 60 to 70 per cent of the total body weight consists of water. Thus, the body of a 65 kg person contains approximately 40 litres of water. Of this, about 25 litres are within the cells and the remaining 15 litres the extracellular fluids.

Functions of water?

Water is essential to the composition of the body for the smooth functioning of the different processes. It helps absorption of the food materials through the intestinal tract. It keeps blood in a liquid state thus enabling easy circulation even in the tiniest blood vessels. Water maintains body temperature constantly at 98.4 Fahrenheit in all weathers and keep the skin moist and cold. It always keeps the mucous membrane moist and helps to secret different fluids in various glands of the body.

Water helps the kidneys to remove unwanted body waste like urea and salt in the form of urine. It also helps removal of body wastes through lungs as water vapour, through skin as perspiration and sweat and, to a small extent through the large intestine as feaces. It is estimated that as much as 37 gallons of fluids are daily filtered off from the blood and restore to the body by kidneys, only when there is proper proportion of water in the blood.

Water Intake

Water consumption is mainly through drinking water, other fluids and water content in the food consumed. Some of our common vegetables contain as much water as milk and even more thus, 100 grams of melon, tomato, and radish contain over 90% of water against only 87% of the water content in milk. Besides taking water through drinks, and in foods, the body itself generate water by the combustion going on in the system.

The rate at which water is eliminated from the body must be replaced by its intake so as to maintain the balance in the system. On occasions, water content of the body suffers considerable fluctuation. Running and other strenuous exercises cause a great loss of perspiration and through the lungs. This loss has to be replaced by a drink of food.

Any great variation in the normal quantity of water in the body interferes with the vital processes and causes acute stress. Death may occur within 3 days of abstention from water. Loss of water takes place, no matter whether we drink or not. So if we do not drink sufficient water, blood thickens and the kidneys fail to deal with it efficiently. This may result in the accumulation of poisons and lead to death. Some persons unconsciously form a habit of living on less than optimum quantity of water. This may lead to ill health and symptoms like headache, nervousness, loss of appetite, digestive disturbances and lack of concentration in work. These symptoms will rapidly disappear with proper intake of water.

What amount of water a person should be taken for the maintenance of good health?

For the maintenance of good health, an adult should take 8 to 10 glasses of pure fresh water daily, weather one feels thirsty or not. This quantity is enough to flush the body and meet all internal needs. However, it is bad to drink excess of water also since it weakens the kidneys and stomach.

Drinking water between meals is good or bad for health?

Drinking water along with meals is not healthy, it dilutes the gastric juices and hampers digestion . Water should be drink half an hour before or an hour after a meal.

Drinking a glass of water early in the morning after a mouth wash is good for our health. It prevents stomach disorders and constipation. Scientifically, drinking water early in the morning helps saliva formation which together with some useful enzymes helps in effective cleaning of the intestinal tract. The age old practice of drinking water in copper vessel early morning is one of the oldest methods with the same principle.


Invisible perspiration carries noxious substances with it and while the water evaporates, the poisonous substances remains on the surface of the skin, sometimes on the pores of themselves. A bath is very necessary not only to wash off these poisonous matter from the skin, but also for keeping the skin in a healthy condition. Cold water or water at body temperature should be used for bathing. The application of cold water followed by friction facilitates rush of blood to the skin. This gives the skin it’s necessary exercise and keeps it healthy and capable of normal functioning of the rest of the day.

Which water should be used ?

Any water, however, is not good. Water used for drinking, cooking and bathing should be free from bacteria, dissolved mineral impurities and suspended matter. Rain water is the best for drinking purpose. Purified water from a river, a spring well or a lake is equally good. Clear water must be further treated if the water is from open sources like river or large over- flooded tanks, there is always the risk of it being contaminated by bacteria of diseases like dysentery ,typhoid and cholera in such case, water should be rendered harmless by boiling. Constant use of hard water for drinking may cause stomach disorders. It is therefore necessary to remove hardness of water by boiling.