'Hunger' hormone leptin may not be culprit behind obesity

Contrary to the long-held belief, it turns out that leptin action is not the culprit behind making you overeat, and leading to obesity.

Assistant professor Diego Perez-Tilve, PhD, at the University of Cincinnati, who directed the research, said that restoring leptin action will not be effective at reducing obesity because leptin action is normal as opposed to being impaired in obesity.

Leptin is a hormone that plays a role in appetite and weight control. It is produced when we are well fed, and signals to the brain that there is ample energy and therefore reduces eating.

Perez-Tilve said the hormone has been of interest since 1994, when scientists discovered that a particular strain of obese mouse couldn't produce leptin at all, making it hungry all the time.

In the study, the team blocked leptin action in both lean and obese mice. The results were both sets of mice ate more and gained almost similar weight, proving that "leptin action was not impaired in the obese mouse."

The study is published in the science journal Cell Metabolism.