Food sharing is a human universal trait that forms the centerpiece of economic and social life in hunter-gatherer societies. Human livelihoods require sharing at all life stages: to support infancy, childhood, and adolescence, and to help reduce risk of daily food shortfalls in adulthood. Attempts to understand the evolved human life history require an examination of the conditions that led to the evolution of food sharing. We summarize key findings and recent directions, and raise unexplored questions. Past emphases included testing predictions from several evolutionary models, and the role that sharing may have played in shaping human family formation. The functions of sharing fall into two categories: reducing food shortages that come with relying on a difficult foraging niche, and advertising attractive qualities of the donor. New directions include multivariate analyses of larger samples from a variety of diverse small-scale subsistence populations, greater consideration of the interdependency between producing food and sharing it, incorporation of bargaining theory into exchange models, and greater attention to proximate psychological mechanisms. Future studies need to explain cross-cultural variation in sharing norms and behavior and use a variety of methods to better bridge observed sharing patterns with the study of underlying social preferences and beliefs.