Book excerpt: Waisted: The Biology of Body Fat outlines the fascinating, often misunderstood and sometimes controversial biology of fat, otherwise known as adipose tissue. It provides a comprehensive, evidence-based perspective on fat biology and its crucial role in human evolution, health, disease, and society. The content draws upon biomedical, epidemiological, social and evolutionary research to understand the striking relationship between body fat distribution and health outcomes. Using digestible analogies, real-world examples and images, it highlights the multi-faceted relationship between adipose biology and society. Waisted clearly conveys the key concepts and assumptions that can lead to negative perceptions of fat, and reframes these challenges to highlight the underappreciated importance of adipose tissue in humans. Waisted is an accessible yet in-depth exploration of the subject that is suitable for both specialists and non-specialists alike. It is a highly valuable resource for clinicians, health practitioners, biomedical researchers, and students who study adipose biology, obesity, and diseases related to fat dysfunction. This book also provides an interesting sociological and anthropological read for anyone who wants to gain a broader and deeper appreciation of the unique role that adipose tissue plays in human evolution and society, by considering how biological and social factors intersect.