This paper discusses the relationships between social and health care system inequalities analyzing the approach and operational ways used in scientific studies produced after the foundation of Sistema Unico de Saúde (SUS), the Brazilian health care system. A review was conducted having as framework four internationally indexed Brazilian scientific journals, which publish their papers on-line in the Project Scientific Electronic Library Online (SciELO). All empiric research studies on health produced in Brazil from 1988 onwards were included and eight descriptors were used: social inequalities, health inequalities and health concept. The scientific production on the subject focuses on the fact that differences in health status are a direct result of inequalities in access and use of medical services. At the same time, a strong trend towards dealing with social inequalities through traditional economic indicators, such as income was observed.