In the daily environment, every 24 hours, we excrete 1.5 liters of water through urine, evaporate 750 ml of water through skin, lose 400 ml of water through breathing, and excrete 150 ml of water through feces. Our bodies lose 2.8 liters of water every day. If you simply convert it, it seems that you have to replenish so much water every day. In fact, 300 ml of water is produced during daily metabolism. Under normal circumstances, food can provide about 1 liter of water, which adds up to 1.3 liter. In other words, we only need to supplement 1.5 liters of water every day, which is equivalent to drinking 6 glasses of water every day (250 ml per cup). Therefore, we need to drink at least 1.5L of water every day. Water is very important for the normal work of our body functions. Even slight dehydration can cause constipation, headache, limb weakness or mental confusion, which increases the risk of urinary tract infection and kidney calculi. If the amount of water pumped into the body reaches 1%, it may lead to an increase in body temperature and difficulty in concentration. When the human body loses 1%-2% water, the thirst mechanism comes into play. If the thirst reflex is ignored, the human body will continue to dehydrate. When the human body lacks 3% water, the body and mind will be seriously affected and cannot function normally. Sports nutritionists have found that when the body lacks 3% water, muscle strength will decrease by 8%. . Dr. Nair Hood, a mineral nutrition expert at the University of Surrey, pointed out that drinking more water will not cause leaching loss of mineral elements in the human body. At present, there is no evidence and reason to prove that drinking more water will lose minerals. However, drinking too much water is harmful to our health. In the daily environment, drinking more than 8 cups a day (that is, more than the body needs) is harmful to the body. Because too much water will increase the burden on the kidneys and may lead to water poisoning, and in extreme cases, it will lead to death. It is reported that a man died after drinking 10 liter of water within a few hours. Every year, many people die of drinking too much water for fear of lack of water while taking hallucinogens. Drugs such as hallucinogens will disturb the normal thirst reflex, and more people will die because they drink too little water after taking them. It is reported that a Hong Kong 16-year-old girl drank 20 liters of distilled water a day for beauty treatment, and was finally admitted to hospital in a coma due to drinking too much water. The doctor pointed out that after drinking a lot of water, people are prone to fatigue, their appetite is greatly reduced, and people feel groggy. This is because drinking too much water dilutes the blood, and the whole body cell gas exchange will be affected. Once brain cells are deprived of oxygen, people will become dull. Experts say that people with normal renal function can only excrete 10~20 liters of urine at most every day. If you drink too much water, the kidneys can't excrete excess water, and the accumulated water in the body will dilute the blood, leading to hyponatremia. Because sodium is an important electrolyte to maintain the osmotic pressure of human cells, hyponatremia will affect various functions of the body. It should be pointed out that pregnant women should also drink water in moderation. Drinking too much water in pregnant women can cause or aggravate edema. It is more appropriate for pregnant women to drink 1~ 1.5 liter of water every day, and it is best not to exceed 1 liter in the third trimester. So, how much water is the most suitable for ordinary people to drink every day? According to experts, the amount of drinking water per person depends on the individual situation, and generally 1.5~2 liters is appropriate. Drinking too much water or drinking too fast at a time is not good for your health, especially for the elderly. Drinking too much water at a time will increase the burden on the heart and kidneys, which is most harmful to people with heart disease, hypertension, kidney disease and edema. It is not advisable to drink too much water at a time after sweating heavily due to labor or exercise.