With the increasing global prevalence of obesity and its associated chronic diseases due in part to poor nutritional habits, addressing unhealthy eating behaviors has become imperative. This chapter explores the integration of sustainability marketing and social marketing to promote healthy diets and advance social sustainability, particularly in alignment with the United Nations Sustainable Development Goal 3 (SDG3), which aims to ensure good health and well-being for all. By leveraging the social marketing benchmark criteria—behavioral objectives, customer orientation, theory, insight, exchange, competition, segmentation, and marketing mix. The primary research objective of this study was to determine the application of social marketing benchmark criteria in the development of effective initiatives that address unhealthy eating behaviors as a social sustainability challenge. Six articles emerged from the application of inclusion and exclusion criteria in a systematic review of studies after 2012 that empirically measured the effectiveness of social marketing initiatives aimed at addressing unhealthy eating. The findings reveal five successful initiatives and one unsuccessful initiative. The successful initiatives included multiple benchmark criteria, emphasizing the importance of a comprehensive, theory-driven approach. This study provides insights into the application of benchmark criteria in the creation of effective initiatives to address the social sustainability challenges of unhealthy eating.