The physiological function of kidney is mainly to excrete metabolic wastes, maintain water-electrolyte balance, endocrine function and so on. 1. Discharge metabolic wastes: kidneys produce urine, in which there are a lot of wastes such as creatinine, creatine, urea, etc. Normal people’s average daily urinary output is about 2000ml. 2. Maintaining water-electrolyte balance: human beings will absorb a lot of nutrients during the process of eating and digestion, such as proteins, fats, sugars, etc., which will produce a lot of acidic and alkaline substances after metabolism, which need to be eliminated from the body through the kidneys. 3. Endocrine function: Kidneys have endocrine function, which can continuously secrete hormone substances, such as bradykinin, prostaglandin, renin, erythropoietin and so on. Kidney is an important organ of human body, so try to avoid drinking alcohol in daily life, and eat less spicy and stimulating food, do some exercise properly, avoid staying up all night, staying up all night is harmful to the kidneys. If you have any symptoms of physical discomfort, you should go to the hospital in time and consult your physician for guidance.