At the end of the Middle Ages, in 1492, the Hôtel-Dieu de Paris was still and establishment of charity intended to receive thepoor which came there to find a shelter and some food. Three centuries later, just before the French Revolution, it became an establishment of care mainly destined to receive the patients, to feed them, take care of them and if possible cure them. This medicalization of the Hôtel-Dieu de Paris is related to the progressive emergence of the medical function, which resulted in the creation and the development of a doctor's and surgeon's profession, but also in the development of the apothecary and its drugs. In this context, the diet plays a central part, because it happens to supplies. It would not be until the eve of the French Revolution that it would be integrated in the doctor's prescription and became a dietetic item.