At a time when public authorities are emphasizing the themes of food and health through the National Nutrition and Health Program (PNNS 1 and PNNS 2)—notably by providing the public with dietary guidelines—closely observing the eating habits of our contemporaries and how they are changing is essential in more ways than one. This snapshot of the situation should facilitate the development of nutritional messages by grounding them in the reality of current practices and enable their targeting toward the social groups that need them most. Furthermore, the dynamic perspective offered by comparing the results of various Health and Nutrition Barometers is a key component in evaluating the impact of public policy on nutrition. The quantitative study of dietary practices originated in the mid-19th century through a three-pronged movement: the application of statistics to social phenomena by the mathematician and sociologist Adolphe Quételet, the interest shown by the economist Ernst Engel in the structure of household budgets, and the development of hygienist thought, which, against a backdrop of scientific progress, supported the rise of social epidemiology. Gaining a better understanding of how people feed themselves, how they spend their money on food, housing, clothing, and so on, means being able to help them—especially the poorest—by encouraging them to better manage their budgets for the benefit of their health and the well-being of their families. This tradition continued after the institutionalization of sociology; thus, between the two world wars, Maurice Halbwachs conducted a major quantitative survey on the living conditions of workers, in which food played a central role. In 1956, INSEE and Crédoc conducted the first national survey on “family budgets.” It was repeated with the assistance of the European Communities in 1963. The following year, INSEE established two ongoing surveys: the first on family budgets and the second on food consumption itself. [excerpt from chapter]