The series originated in the United Kingdom on ITV in 2002 as Fat Club, with members of the general public taking part.
There was also no host as such, although comedian Jenny Eclair provided a voiceover with the filmed advice of nutritionists Dr Adam Carey and Matt Lovell throughout the series.
In this series, former Fit Club contestants joined the judging panel, with a different ex-contestant appearing each week: so far, they have included Amy Lamé, Aldo Zilli, Jonathan "Jono" Coleman, Paul Ross, Alison Hammond, James Whitaker, Lowri Turner, Ann Widdecombe and Kym Mazelle.
Also this year the final episode is a 90-minute mini-Olympic event in Sheffield, where Channel 4's The Games takes place, with past celebrities joining the two teams.
Russell Grant, severely morbidly obese at 21 st 11 lb (305 pounds (138 kg)), admits that from 10:30am to 9pm daily he is constantly snacking, regardless of whether he is hungry or not.
Sharon Marshall, 13 st 4 lb (186 pounds (84 kg)) admits to a 'booze' problem and a lifestyle of parties which is not helping her weight loss.
Mick Quinn, once at the peak of physical fitness as a professional footballer, has, since retiring from sport, ballooned to 19 st 6 lb (272 pounds (123 kg)), making him medically morbidly obese.
Jeff Rudom, former professional basketball player, was 7' 1" (216 cm) tall and weighed in at 32 st and 7 lb (455 pounds (206 kg)), making him the tallest and heaviest celebrity ever to appear on the show.
Fellow contestant Carole Malone branded Anne "a cheat", and she was subsequently banned from the team weigh by the other celebrities.
At the weigh-in, Dale dealt some bad news: as he approached the finish, Mick had thrown the baton before he had crossed the line, thus disqualifying him from the race, and giving the win to the opposing team.