Water is fundamental to our health and well-being. Its importance to a well-functioning body is often overlooked by many. It has two major purposes in the body - it assists the transportation of nutrients to the cells of the body and the transportation of waste products and toxins out of the body.
Even slight dehydration can have an effect on the physiological function of the body. When testing a person's quantum reflex, they can test weak if dehydrated and will generally always test stronger after having a glass of water which shows the instantaneous affect water has on our well-being. If you feel thirsty you have already become dehydrated, so stay hydrated rather than waiting for your body to have to blatantly signal you with thirst.
Although you do get water from consuming any type of drink, it is not the same as having pure water because the body then has to work to break down the different components of the drink (however herb teas are ok as they are a good nutritive form of water). Coffee, tea and alcohol have a diuretic effect on the body, so they can actually cause you to become more dehydrated therefore increasing your need for more water. Exercise can also increase the need for more water. Adding electrolytes to your water is a great way to rapidly rehydrate.
So don't take water for granted... nature provided it for a reason and without it we wouldn't be alive. It's free and readily available to most people, so do yourself a favour and drink more water on a regular basis.