This thesis explores the history of healthy eating in the mid-to-late twentieth century, providing insight into the roots of contemporary anxieties about healthy lifestyles, dieting, and the prevention of chronic disease in the UK and the US. This thesis argues that during the post-war decades, British and American societies experienced a fundamental shift that enabled new forms of cultural preoccupations about health and diet to flourish. This shift created an obsession within the media, science and society about safeguarding good health, youth and vitality, especially through dieting, specific foods, and the ingestion of supplements. This shift was enabled by the simultaneous promotion and representation of healthy eating as a solution to chronic diseases, by neoromantic notions of health, by anxieties about modern living, but also by the growth of ideas around individual agency and responsibility for health. Drawing on a rich source base of self-help books, newspapers and magazines, advertisements, medical journals and comic books, chapters of this thesis explore the ways in which contemporary obsessions about diet and health were promoted, reported on and experienced in everyday life. Examining health obsessions in relation to gendered approaches to food and broader post-war concerns about the impact of modernity on health and lifestyle, on the valorisation of slim bodies and youth, and on chronic disease prevention and productivity, this thesis offers new perspectives on the multifaceted interactions between self-help advice literature, newspapers and magazines, mainstream medical thought, and comic books during the postwar decades.Wellcome TrustWellcome Trus