The human body needs to replenish certain amount of water in time every day, which is good for accelerating blood circulation, urination and sweating, promoting digestion and speeding up metabolism, which has an important role in promoting the health of the body, and also has a preventive effect on some diseases, such as colds, urinary tract infections, gout, kidney stones, etc. Drinking 2 liters of water a day, after 1 month may show skin improvement, making the skin more hydrated, fair as well as elastic; in the case of constipated patients, the situation of difficult bowel movements will improve. Because the waste in the body can be excreted with the urine, thus benefiting the health. However, it also needs to be accompanied by a good lifestyle, such as early to bed and early to rise, a healthy diet, proper exercise, and a combination of work and rest. Note that drinking 2 liters of water a day does not apply to everyone. Studies show that normal people need to drink an average of 1.5-2 liters of water per day, which can be adjusted according to the actual situation. But for some people, such as renal insufficiency, heart failure, liver function abnormalities and other patients, drink 2 liters of water per day, may lead to aggravation of the disease or cause other complications, should be reduced according to the condition of the daily water intake, so as not to aggravate the disease. In addition, drinking water should pay attention to the scientific way, should be a small number of times to drink water, and not wait for thirst before drinking water, and not a one-time replenishment of the entire amount of water, before bedtime, after strenuous exercise and other cases should be reduced to drink water. It is recommended to drink more warm water, as little as possible to drink too cold, too hot water, so as not to stimulate the stomach and intestines or cause burns.