The brain is hardwired to stop people from drinking more water than is healthy, according to a recent study.

Researchers from the University of Melbourne found that there is a "stop mechanism" in the brain that tells the individual to stop drinking water when no longer thirsty. They also found the effects of drinking more water than required.

Drinking too much water can reduce salt concentration of the blood that can result in the swelling of the brain, a potentially fatal condition. The condition, also known as polydipsia, has been found in some patients with schizophrenia and in some marathon runners, according to a press release.

"Different areas of the brain involved in emotional decision-making were activated when people drank water after becoming thirsty and when study participants followed instructions to keep drinking when no longer thirsty," Derek Denton, researcher and professor at the Faculty of Medicine, Dentistry and Health Sciences at the University of Melbourne, said in a statement.

For the study, researchers used magnetic resonance imaging to scan two physiological conditions of the brain, starting with scanning brain regions during the experience of thirst. Study participants were then removed from the scanner and asked to drink to satiation or "overdrink" and returned for further scanning.

He said the brain regions determining the signals to stop drinking have not previously been recognized in this context.

"It identifies an important component in regulation and this 'stop mechanism' may prevent complications from excessive water intake," Denton added.

He also said the findings provide insight into the human instincts that determine survival behavior and are also of medical importance.

"This is a study of elements of gratification and how the body programs accurate behavior. In revealing aspects of gratification control, the data are relevant to study the gratification of other instincts, such as food intake, salt intake and sexual behavior," he said.