An NHS-backed scheme has paid out tens of thousands of pounds in "air miles for dieters" in a drive to tackle the obesity crisis.
Now more people are being recruited to the programme, which pays a maximum of 3,000 for those with the most to lose.
Under the Weight Wins scheme, overweight people sign up for a slimming programme and have monthly weigh-ins at their GP surgery, pharmacy or fitness centre.
They earn cash payments for every pound they lose while dieting and then a 50 per cent "bonus" if they manage to keep the weight off for several months.
Final rewards range from 80 to 3,000, depending upon the length of the plan and how much weight the dieter needs to lose.
People can either pay a monthly fee or they can be sponsored by their employer, insurer or local NHS trust.
Data published today on 745 dieters found people lost more than a stone on average.
This was more than double that of traditional dieters in a control group (5.5lb).
The guinea pigs include 402 people sponsored by NHS Eastern and Coastal Kent Primary Care Trust as part of a pilot, 36 per cent of whom were men.