This chapter examines how socioeconomic–demographic factors shape dietary behaviors using examples from maternal nutrition during pregnancy. Dietary behaviors—encompassing eating habits, food choices, and dietary intake—are shaped by the interaction between individual characteristics and broader contextual determinants, such as economic systems, cultural norms, and policies. Socioeconomic–demographic factors, including education, income, marital status, and parity, are measurable characteristics that represent the individual realities within a large context affecting dietary behavior and health outcomes. Drawing on examples from pregnancy, the chapter explores how these factors influence food consumption patterns, portion sizes, diet quality, and eating motivators, among other things. It emphasizes the need for a conceptual framework to analyze how socioeconomic–demographic factors act as direct drivers, confounders, mediators, or moderators of dietary behaviors. Such a framework provides critical insights for understanding the root causes of dietary behavior differences and identifying opportunities for intervention. By contextualizing dietary behaviors within socioeconomic and demographic realities, this chapter calls for strategies that consider the unique needs of different populations while promoting socially inclusive and effective solutions.