Dehydration

Water: an Essential Nutrient
Water is the single most important nutrient in our lives. This vital nutrient makes up 50% to 65% of the human body (Pacific Northwest National Laboratory 2007). Without water, a human being will only last a few days before dying from dehydration (Internet Health Library 2001). Water plays a very essential role in the everyday functions of our day-to-day activities. Because of this, individuals who lack the water they need to perform these functions are inevitably going to run into complications.
Functions of water
One function of water in our body is that it is used as a lubricant between joints and around our organs. This keeps everything moist which allows for a smoother operation of both the joints and the organs. There is a thin layer of water that surrounds our brain, eyes, and spinal cord (among other organs) that is very important in protecting and maintaining their structure.
Another function that water serves in our body is the regulation of our body temperature. It is very important that our body is maintained within a certain temperature. Water performs this function quite well by absorbing heat and perspiring through our skin pours.
Water also serves as the mode of transportation to deliver vital vitamins and nutrients throughout our body. Without water, our organs, muscles, bones etc. would not get the much needed supplies to allow the body to function properly.
An additional function that water serves in our body is that it aids the digestion and waste removal process in a number of ways. When food first enters the mouth to begin the digestion process, it is met by saliva which is primarily made up of water.