In this interview, David Kessler, former commissioner of the Food and Drug Administration, explains why so many people overeat. Changing lifestyles promote the constant availability of food and around-the-clock eating. In today's highly processed foods, food companies are able to dial in the exact amount of fat, sugar, and salt that will make people come back for more. We're no longer eating for nutrition or fuel--we're eating for reward. Schools can help rectify this situation by teaching students about good nutrition so they will want to eat foods that will sustain, satisfy, and nourish them.