The need for proper intake of water can never be overemphasized. It is obvious that without water there will be no life. Nearly all metabolic activities in the human body needs water and without it metabolism ceases and as a result, life also stops.
Human beings loose a lot of water to their surroundings through a lot of processes which include respiration, excretion, perspiration, etc. Therefore to replenish these loss, one needs to ensure adequate intake of water regularly to avoid dehydration.
The human blood consists approximately 90% of water among other constituents, therefore adequate intake of water helps to maintain this balance and will also help to avoid too much concentration of solutes in the blood. Proper water intake is also vital in maintaining a healthy kidney. The kidney is the organ for excretion with the sole duty of filtering every waste product of metabolism from the blood and other tissues in the body. It carries out this function in a series of steps under ultrafiltration. Here, the kidney carefully filters out every ion, salts and other waste product not needed in the blood as it passes through the kidney. Assuming one do not always take in enough water, some of these ions and salts tends to accumulate in the kidney unknown to the casualty until it deposits in such amount that it begins to block the kidney ducts and the fellow starts having kidney failures.But inasmuch as one takes in enough water, it helps to wash away these salts thereby preventing their accumulation and thus, the kidney functions well.
Improper water intake also dehydrates the body leading to shrinkage of the cells ( plasmolysis) and an outward wrinkling of the skin making one look older than his age.
In summary most cellular activities takes place effectively when the body cells are turgid, therefore it is advisable to drink water always in order to maintain their efficiency.