Fat is much more than a physical imperfection, practical inconvenience, or health risk. Instead, it is a fascinating, mysterious, and misunderstood tissue that represents an ancient link between energy metabolism, reproductive biology, immunity, appetite, and even thermoregulation. It also forms the foundation of the curves which define the archetypal human female and male body shapes, which have since enabled the human body to transcend mere physicality and become social, economic, and political barometers. Laden with increasingly complex, nuanced, and even paradoxical meanings, mounting evidence indicates that the amount and distribution of fat not only provide our body with a distinctive shape, but are also a strong determinant of our health. Adipose tissue carries many negative connotations due to the numerous ailments associated with having too much of it, but it is not inherently bad. On the contrary, it has a legacy that clearly indicates it is essential for life.