Scientists from the Université de Montréal are developing a weight loss pill composed of leptin, the protein that regulates appetite in mammals. The researchers say that leptin may be a good weight loss pill because its levels decrease when we fast and rise when we eat, meaning that increasing them could reduce people's urge to continue eating. The protein has also been proven to suppress appetite when administered intravenously to pathologically obese people.

"Taken orally, such a pill would provide obese people with the sensation of being full. They would eat less and in turn lose weight," says Dr. Cammisotto, one of the researchers on the project.

"Obesity is a big problem in our society, no pun intended," says Moïse Bendayan, a pathology professor at the Université de Montréal. "To develop medication to combat obesity would be a great way for our laboratory to contribute to public health."

The new pill is being created based on a discovery made in 2006 that leptin isn't only secreted by fatty tissues. "From the first bite of any meal, leptin levels skyrocket in the bloodstream. Yet this has nothing to do with the leptin stored in the fatty tissues," says Bendayan. "In the lab, we proved that up to 80 percent of cells in our stomach also produce leptin. Those are the ones that regulate appetite."

The finding led to a different understanding of how the protein works, since leptin alone can't survive in an acidic stomach without assistance. Indeed, leptin protects itself with an accomplice that acts as its bodyguard and accompanies the protein through the digestive system until it can be absorbed into the bloodstream.