thirst centre

The thirst center is located in the hypothalamus, a region of the brain that plays a crucial role in regulating bodily functions. This center is responsible for the sensation of thirst, which prompts us to drink fluids.

When the body becomes dehydrated, the concentration of dissolved substances in the blood (serum osmolality) increases. This change is detected by specialized nerve cells called osmoreceptors in the hypothalamus. These osmoreceptors, which are closely linked to the thirst center, are stimulated by high osmolality, triggering the sensation of thirst.

Conversely, when the body is overhydrated, serum osmolality decreases, inhibiting the osmoreceptors and reducing the urge to drink. The hypothalamus also works with the pituitary gland to control water balance through the hormone vasopressin, which helps the kidneys retain water. A rare disorder called adipsia occurs when damage to the hypothalamus's thirst center results in a lack of thirst, even during dehydration.123