Every body cell, tissue, organ, and nearly every life-sustaining body process requires water. Water helps to control body temperature. Perspiration keeps us cool in hot weather and protects the body against heat exhaustion.
Water helps the body to insulate itself against cold weather.
Water carries nutrients to body cells and carries away waste. Water promotes better digestion and intestinal function. Water keeps mouth, nose, eyes, and skin moist. Water ensures proper volume of blood. Water keeps the urinary tract flushed out.