The food choices consumers make have considerable consequences for the environment. In the Western world, about one-third of all negative environmental impact is directly related to food consumption. Although many consumers are concerned about environmental issues, this frequently has little effect on actual nutritional behavior and new approaches are needed to convert good intentions into action. Gamification could be a possible way to encourage both self-efficacy on the part of the consumer as well as normalizing such behavior socially. In this paper, central elements of the behavioral change model HAPA (health action process approach) are introduced to a gamification concept. The underlying frameworks of both concepts are then analyzed in order to develop propositions for use in the design of an effective gamification setting to promote sustainable nutritional behavior (SNB).