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Scientists find hunger hormone

Scientists find hunger hormone

LONDON, England -- Scientists say they have discovered a hormone that prevents the feeling of hunger.

A natural chemical, known as PYY3-36, is normally released by the gut after eating in proportion to the amount of calories consumed.

It sends signals to the feeding circuits in the brain that convey a sense of satiety that reduces the urge to eat.

The find could lead to a new generation of safer and more effective slimming treatments for some of the one billion people around the world who are overweight or obese.

A British-led team of international researchers injected the hormone into the bloodstream of a test group and found that it tricked the brain into thinking the stomach was full.

Professor Stephen Bloom, from Imperial College London, who led the research, said: "The discovery that PYY3-36 suppresses appetite could be of huge benefit to those struggling with weight problems.

"It's what stops you having the third helping. With over a billion people across the world now extremely overweight, it is vital this problem is tackled.

Chart: BMI weight-to-height 

Dr. Sanjay Gupta on the hunger hormone  discovery

Obesity is based on body mass index (BMI), which is calculated by dividing weight in kilograms by height in metres squared. A BMI of more than 30 is considered obese.

People who are overweight are at risk of other health problems, including diabetes, heart disease, strokes and certain cancers.

In the tests, 12 volunteers were infused with either PYY3-36 or salty water in a trial at Hammersmith Hospital, in west London.

Two hours later, they were offered an unlimited buffet meal. The hormone group's average calorie intake dropped by a third over the next 24 hours.

Those who were given PYY3-36 also reported an up to 40 percent drop in their feelings of hunger for 12 hours after the treatment.

The research, published in the journal Nature, is part of an ongoing investigation at Imperial College into human drives such as appetite.

Team member Dr Rachel Batterham said: "The results show the hormone PYY3-36 could help in tackling the problem of obesity.

"Rather than using extreme measures such as dieting pills, or even surgery, PYY3-36 should be able to provide a far safer and effective alternative."

Professor Rory Shaw, medical director at Hammersmith Hospital, said: "We have always known that hunger is determined by complex interactions between the brain, hormones and enzymes in the gut.

"But this discovery -- that administering a particular hormone can actually reduce appetite -- is a major step forward on the road to the development of a new, safe and effective treatment for obesity."

Bloom said: "It may be possible to identify foods which cause the release of more PYY3-36, helping to naturally limit appetite, or it may be possible to create a tablet with a similar effect, providing an excellent, natural and safe long-term treatment for obesity."


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