A much-discussed work that sold 200,000 copies and ignited the “low-carb boom” in Japan. The author, a doctor, maintains a low carbohydrate diet himself and squarely refutes rumors that “low-carb is bad for the health.” The rationale for restricting carbohydrates is explained not only from medical and nutritional perspectives but numerous other viewpoints, including the history of consumption of carbohydrates. The experiences of many practitioners are also shared.