Normally the body regulates its water content by balancing the intake of fluids (through thirst ) and its elimination (through the production of urine ). When the amount of water in the blood is low, for example after excessive sweating or loss of blood due to bleeding, the thirst center is stimulated. And until balance is restored, cells called osmosensory cells order the release by the hypothalamus of vasopressin , an antidiuretic hormone that orders the body to retain as much fluid as possible.
Researchers at the McGill University Health Center in Quebec (Canada) have found that, during nighttime sleep, our internal clock , located in a structure of the brain known as the suprachiasmatic nucleus, induces a considerable increase in vasopressin levels . This makes us retain enough water and prevents us from becoming dehydrated during rest time without the need to drink, as revealed in an article published in the journal Nature .
