Walter Willet, M.D. Professor of Epidemiology and Nutrition and Chairman of the Department of Nutrition, Harvard University School of Public Health
"The current history of the dietary pyramid is based on: all 'complex' carbohydrates are good, all fats are bad. That view was never supported by any (scientific) data. Until recently, it has been believed that carbohydrates should be thought of as sugars and complex carbohydrates: the sugars are bad and the complex carbohydrates are good. But that now seems far too simplistic because many of the complex carbohydrates, like potatoes and white bread, are converted rapidly to glucose (a sugar) once we eat them. In fact, it's likely that these foods are even worse than sugar, since they actually result in more rapid rise in glucose than sugar itself does."
