Water operates in the body mainly through the mouth, stomach, intestines, liver, blood, heart, lungs, kidneys, and excretory system. Water is one of the most important nutrients. Water accounts for about 60% of the body’s weight and provides the prerequisites for the body’s metabolism. Water initially begins to reach the body’s stomach via the digestive tract and then reaches the intestines, liver, blood, heart, lungs, kidneys, and excretory system to complete in turn. Water is partially absorbed as it passes through the stomach and small intestine, most of it is absorbed in the large intestine, and a small portion is excreted from the body through the anus via the feces. Water absorbed by the stomach and intestines enters the circulation and then moves between tissue fluid, blood, and intracellular fluid, a process that depends on the amount of intercellular osmotic pressure. Some of this water is used to participate in chemical reactions in the body and to carry out the body’s metabolism. A portion of the water is transported through the bloodstream to the kidneys, where it is filtered by the glomeruli, and a portion of it is excreted in the urine, which is the predominant route of excretion. A portion of the water enters the skin, and due to the difference in temperature between the inside and outside of the body, a constant stream of water is emitted from the surface of the body through the skin, i.e., sweat. A portion of water is excreted through respiration, which is also responsible for the water vapor contained in the body’s exhaled gas. There are some other pathways such as tears and runny nose. If your body has abnormal water metabolism, please consult the hospital in time to avoid delay.