Dr Christian flies out to Evansville, Indiana, officially America's 'Fattest City', where 38% of the population is obese. Experts predict that by 2020 a third of adults in the UK will be obese. But in America this milestone has already been reached. He meets a woman who lost her foot to obesity-related diabetes, and visits a funeral home where the coffins are the size of hot tubs! In the Feeding Clinic, Supersize and Superskinny go on a shocking diet swap. But before they swap diets, Christian gives his Supersizer a terrifying glimpse into the future by sending them to the US, to spend time with somebody whose obesity has ruined their life. The new series also examines a variety of eating disorders as six men and women reveal their very personal stories. In this episode, 18-year-old it's Ellie Lambert, whose anorexia was triggered by a jaw operation that prevented her from eating.