A Matter of Fat is a 1969 documentary film by William Weintraub chronicling the efforts of a 358-pound man, Gilles Lorrain, to lose half his body weight as part of a hospital supervised weight loss program. In the film, Lorrain recounts his life and experiences, often with humour. In one 21-second time lapse sequence, Weintraub shows Lorrain's 150-pound weight loss, filmed at two frames a day for seven months. The film also shows Lorrain's return to his family after the gruelling program, and his conviction that he will be one of one in four dieters who can keep the weight off.