It's an emotional rollercoaster in the feeding clinic as Supersize cheese addict Stu Preston takes on Superskinny portion controller Alice Duran. At 27 stone 13lbs Stu is digging himself an early grave with a knife and fork and desperately needs help. Twenty-five-year-old mum of two Alice weighs a lightweight 7 stone 13lbs by obsessively controlling her diet and weighing her food but she's hiding a supersize secret, she once weighed a staggering 17 stone. Stu's deadly diet of fast food and excess cheese pushes Alice into meltdown and Dr Christian wades in to confront her about her food phobias. Plus eating disorder dietician Ursula Philpot asks the show's group of eating disordered people to look back to childhood times when eating was enjoyable, which forces the girls to face up to the fact food should be fun.

• Liza Tarbuck
• Anna Ryder Richardson
• Gillian McKeith