This article analyzes the Social Determinants of Health as structural mechanisms that produce and reproduce disease and social inequality. Departing from a critical perspective of the health–disease process, the text argues that health outcomes are not randomly distributed, but rather reflect historically constructed social, economic, political, and cultural arrangements. Through a theoretical and reflective academic essay, the article examines how income, education, work, housing, territory, gender, and race interact in cumulative and interdependent ways, shaping unequal life chances and health trajectories. The discussion emphasizes that illness cannot be understood solely as a biological phenomenon, but as a socially produced condition deeply embedded in power relations and structural deprivation. Health inequities are presented as systematic, avoidable, and unjust differences that disproportionately affect socially marginalized groups, revealing the political nature of disease distribution. The article also highlights the limitations of fragmented and market-oriented health systems, which tend to address the consequences rather than the structural causes of illness. Finally, the text discusses the implications of social determinants for public policies, underscoring the need for intersectoral action, social participation, and equity-oriented strategies. The incorporation of social determinants into health planning is presented as an ethical, political, and technical challenge, essential for reaffirming health as a fundamental human right and for building more just and sustainable societies.