In this chapter, we examine the influence of new materialist theories and methodologies on emerging debates concerning obesity as a phenomenon that is entangled with the biopolitical conditions of life and knowledge production. We discuss how new materialist styles of thought draw upon various post-humanist and post-qualitative approaches to reorient the onto-epistemological assumptions of humanist critique to question how bodies come to matter (as fat, obese, normalised, pleasurable, disgusting, visceral, physiological, visual, mobile, and subject to intervention). The chapter explores the implications of these ideas for research, policy, and practice across health, education, and popular culture, highlighting their potential for opening new ways of thinking, doing, and being across these areas.