It has become something of a scholarly truism that during the medieval period, gluttony was combatted simply by teaching and practicing abstinence. However, this dissertation presents a more nuanced view on the matter. Its aim is to examine the manner in which the moral discourse of dietary moderation in late medieval England captured subtle nuances of bodily behavior and was used to explore the complex relationship between the individual and society. The works examined foreground the difficulty of differentiating bodily needs from gluttonous desire. They show that moderation cannot be practiced by simply refraining from food and drink. By refiguring the idea of moderation, these works explore how the individual’s ability to exercise moral discretion and make better dietary choices can be improved. The introductory chapter provides an overview of how the idea of dietary moderation in late fourteenth- and fifteenth-century Middle English didactic literature was influenced by the monastic and ascetic tradition and how late medieval authors revisited the issue of moderation and encouraged readers to reevaluate their eating and drinking habits and pursue lifestyle changes. The second chapter focuses on Langland’s discussion in Piers Plowman of the importance of dietary moderation as a supplementary virtue of charity in terms of creating a sustainable community. The third chapter examines Chaucer’s critique of the rhetoric of moderation in the speech of the Pardoner and the Friar John in the Summoner’s Tale, who attempted to assert their clerical superiority and cover up their gluttony by preaching moderation. The fourth chapter discusses how late Middle English conduct literature, such as Lydgate’s Dietary, revaluates moderation as a social skill. The fifth chapter explores the issue of women’s capacity to control their appetite and achieve moderation in conduct books written for women. Collectively, the study illuminates how the idea of moderation adopted and challenged traditional models of self-discipline regarding eating and drinking in order to improve the laity’s discretion and capacity to assess its own appetite and develop a healthy lifestyle for the community.