Losing weight might be as easy as chewing gum, according to British scientists. Researchers at Britain's National Health Service say they have developed a chewing gum that will suppress the appetite of anyone using it.

The researchers say it works by releasing a substance into the body that makes the user feel full. The substance is based on the body's actual hormone that tells the brain to stop eating once a large meal is consumed.

The drug may soon be available in Britain, where rising obesity levels have led to a large increase in a number of related diseases and have threatened to swamp the nation's state-run health service. The drug is designed to be absorbed through the mouth, making chewing gum an ideal delivery vehicle, researchers say.

Laboratory tests so far have been encouraging. Human volunteers who were given the drug reduced their food consumption 15 to 20 percent without feeling hungry. Mice who were administered the drug lost 15 percent of their body weight in one week's time.

Researchers say more testing is needed, but that the drug could be on the market within a few years. They say it could be delivered in a variety of ways besides chewing gum, including as a nasal spray and in injection.