70% of the human body is water. It provides thermoregulation, fills the cells of the body with oxygen and it is the basis of all metabolic processes. Lack of water can lead to poor health and well-being. It follows that water is the basis of our body's vital activity. A person can live without food for many weeks, but without water cannot survive for three days. Therefore, it is necessary to maintain the body's water balance on a daily basis.