The Section of the History of Medicine is a freestanding unit in the Yale University School of Medicine engaged with research and teaching in the history of medicine, the life sciences, and public health. In addition to instruction for medical students, including mentoring M.D. theses, the faculty collaborates with colleagues in the History Department, in the Program in the History of Science and Medicine, which offers graduate programs leading to the M.A., Ph.D., and combined M.D./Ph.D. degrees and an undergraduate major in the History of Science/History of Medicine. The Section contributes to the Program's colloquia, and Distinguished Annual Lectures, workshops, and symposia in medical history. Through research and teaching, the faculty seeks to understand medical ideas, practices, and institutions in their broad social and cultural contexts, and to provide intellectual tools to engage with the challenges faced by contemporary medicine.
Louis Pasteur (1822–1895) was one of the most important founders of medical microbiology. He is remembered for his remarkable breakthroughs in the causes and preventions of diseases. His discoveries reduced mortality from puerperal fever, and he created the first vaccines for rabies and anthrax. His experiments supported the germ theory of disease. He was best known to the general public for inventing a method to treat milk and wine in order to prevent it from causing sickness, a process that came to be called pasteurization. He is regarded as one of the three main founders of microbiology, together with Ferdinand Cohn and Robert Koch. He worked chiefly in Paris and in 1887 founded the Pasteur Institute there to perpetuate his commitment to basic research and its practical applications. As soon as his institute was created, Pasteur brought together scientists with various specialties. The first five departments were directed by Emile Duclaux (general microbiology research) and Charles Chamberland (microbe research applied to hygiene), as well as a biologist, Ilya Ilyich Mechnikov (morphological microbe research) and two physicians, Jacques-Joseph Grancher (rabies) and Emile Roux (technical microbe research). One year after the inauguration of the Institut Pasteur, Roux set up the first course of microbiology ever taught in the world, then entitled Cours de Microbie Technique (Course of microbe research techniques). It became the model for numerous research centers around the world named "Pasteur Institutes."[126][127]

The Greeks also knew that diet and exercise and keeping clean were important for health. Later Alexander the Great conquered Egypt. In 332 BC he founded the city of Alexandria and a great medical school was established there. Doctors in Alexandria dissected human bodies and they gained a much better knowledge of anatomy. However little progress was made in understanding disease.

James pieces together the last twenty five to forty years from the elders of which functional medicine was created. The basis of Functional Medicine is in history of Naturopathic, Chiropractic and Acupuncture along with the nutritional and medical research worlds. The new terminology fits within the paradigm of medicine and allows those in the medical field to grasp the root concepts that have been spoken for the last several hundred to four thousand years. Only now is the science finally catching up to what has been spoken by the elders in those professions.