The main function of this hormone is to regulate the excretion of water by the kidneys. If the hormone is not released at all (as in diabetes insipidus), then a person can lose 20 liters of fluid, although normally this number should be equal to 1.5 liters.
Also, scientists have found that if a person does not drink enough water every day, a person is more likely to develop diabetes mellitus. It can also lead to high vasopressin levels.
The hormone vasopressin has many other functions: it can stop blood, reduce the intensity of pain, participate in the control of aggression, reaction to a stressful situation, and sexual motivation.