Documentary looking at the physiological and psychological pressures people face as they battle the bulge. Using computer graphics to travel inside the body, the film explores the science of fat, how we get it and what happens to our body when we get rid of it. We meet Ebonie, whose crash diet has pushed her body into starvation mode, and follow Joe as he undergoes an extreme liposuction operation where ultrasound technology sculpts fat away to produce his perfect physique. We discover the science behind the diet pills which left Sam in a mental health unit and explore how binge eater Hayley has used food as an emotional prop throughout her life. Through the highs and lows, this is the inside story of 'How Fat Works'.