This article is the first of four on prescientific nutrition and dietetics. The series explores allopathy and the rich prescientific origins of nutrition and dietetics: Part One—the nutritional-dietary legacy of India; Part Two—the allopathic contributions from Greek-Roman-Byzantine; and Jewish-Christian-Moslem Mediterranean societies; Part Three—the allopathic works from China; and Part Four—the important Hispanic contributions to allopathy in the New World. The objectives are three: 1) to identify the ancient origins of allopathy as a medical-dietary system and trace it from antiquity into the 20th century; 2) to identify and describe allopathic principles using original accounts and important readily available secondary sources; and 3) to explore how allopathy and scientific nutrition differ and where common-sense principles coincide. By the development and publication of this series the author and editor believe that nutrition education in the United States today can be improved, especially in American communities where allopathy is widely practiced and science is viewed skeptically.