Fructose is the natural sugar present in fruits. During the last 30 years, large amounts have been incorporated into processed foods and beverages, including low-fat alternatives. It is found in large amounts in anything containing high fructose corn syrup, but this is not the only form. Evidence that fructose causes obesity is piling up. Dr. Robert Lustig, a Professor of paediatric endocrinology at UCSF presents a summary of the proof in a compelling 90 minute lecture.