Loneliness, social isolation, and unhealthy eating are worldwide problems with important implications for health and well-being. The need for interventions to address these issues within individuals, groups, and populations has been highlighted at local, national, and international levels. Less well recognized are the rationales connecting social connection and eating. The purpose of this chapter is to discuss the evidence for associations between loneliness or social isolation and eating and to examine the possible underlying reasons for and direction of any relationships. Varying amounts of research have explored the relationship between loneliness or social isolation and eating behaviors as well as closely related conditions or outcomes including food security, weight status, eating disorders or disordered eating, and malnutrition in adults and children. Connections between loneliness or social isolation and all these areas have been shown; however, they are not entirely consistent. Important gaps and limitations in the evidence remain. Further research is needed on longitudinal connections using validated methods and within underresearched groups such as children and people in low- or middle-income countries, living in institutions or with medical or physical health issues to inform the work of practitioners or organizations aiming to enhance social connection and/or healthy eating.