05/12/2011 GMT
Dec 05, 2011•18 min
Episode description
When leptin failed to be a wonder solution to obesity, this hormone produced by fat cells, disappeared from the headlines.
Twenty years on scientists now believe leptin is critical to how the body works, regulating appetite, the immune response, inflammation and depression.
Vivienne Parry investigates.
For the best experience, listen in Metacast app for iOS or Android
