This session continues Yale's course on food, taught within the university's series examining why people eat the way they do. The lecture builds on earlier sessions covering the biological drives behind hunger and satiety, the psychological triggers that shape cravings and eating habits, and the political and economic forces, including agricultural policy and food industry marketing, that determine what ends up on a plate. Expect discussion of how these three threads intersect, for instance how policy decisions on subsidies or labeling interact with psychological research on portion size and marketing exposure. The format follows a standard university lecture, with the instructor working through material at length rather than in a panel or discussion format. As with other entries in this series, the emphasis is on connecting individual behavior to larger systems, treating obesity and diet not just as personal choices but as outcomes of biology, culture, and public policy working together.