The primary objective of this pragmatic trial was to analyze the effectiveness of health literacy in patients with type 2 Diabetes mellitus (DM2) on a protocol of care in Primary Health Care (PHC) units. The secondary objective was to analyze the effectiveness of knowledge about diabetes, self-efficacy, and glycated hemoglobin (HbA1c) in DM2 patients on a PHC protocol, as compared to the regular care provided by the municipality. Patients from four Family Health Units (FHU) were part of the study, two units as control group (CG) - Usual Assessment, two as intervention group (IG) - Multidisciplinary Assessment, with 44 subjects in each group. The IG mirrors the care protocol, which includes individual visits with physician, nurse, and nutritionist, in addition to systematized collective activities. The CG received the usual care. The research raises the hypothesis that subjects in the IG had a better understanding of aspects related to the disease and were more active in their own health care, as compared to patients who did not receive the intervention.