The human body is made up of about 75 percent water. By drinking up to ten glasses of water a day, the bodily systems, including digestion, metabolism, and absorption, can function properly. Water contains electrolytes, or salts (sodium, potassium, chloride, calcium, magnesium, bicarbonate, phosphate, and sulfate) that are vital to these systems. Electrolytes help cells successfully maintain and transmit impulses within themselves and to other cells. Water is lost from the body through perspiration, urination, and respiration. These processes cannot be stopped, but not replenishing the body with water results in the symptoms of dehydration: excessive thirst, fatigue, headache, dry mouth, dizziness/lightheadedness, infrequent urination, and weakness in the muscles. These are the result of the loss of electrolytes.