Abstract: In a text exploring the allure and danger of nutrition cultism, citizens are encouraged to protect themselves from health frauds and food fads by becoming informed. Nutrition cultism is a multi-billion dollar industry. Food quackery sells because it reaches people's beliefs and emotions. Quacks speak in scientific terms while attacking organized medicine. Part I exposes the propagandist promotion of laetrile as a cancer cure, and the misinformation surrounding megavitamin therapy. Anecdotal claims supporting nutrition cults are seen as worthless, and may contribute to health hazards. Part II discusses ethical considerations in the practice of medicine, prescription of diet and drugs, and scientific inquiry. Part III describes concepts of diet and health promoted by the American Medical Association and National Academy of Sciences. The difficulty of establishing nutritional standards and guidelines, and of educating the public on food and nutrition, is emphasized.