The recommended daily amount of water to drink is six to eight glasses a day. This amount will keep the body hydrated for normal activity. Hydration is important for the body. Water helps to control body temperature, to lubricate joints, and to eliminate waste through perspiration and urination.
When the body becomes dehydrated, perspiration decreases and urination also decreases. Early signs of dehydration include a dry mouth, sleepiness, thirst, dry skin, headache, constipation or dizziness. Because the kidneys help control blood pressure regulation, blood pressure may decrease but heart rate will increase. Rapid breathing is another sign of severe dehydration. Since water controls body temperature, fever may also be present.