Metabolic Syndrome (MS) is a complex disorder characterized by a number of cardiovascular risk factors usually associated with central fat deposition and insulin resistance. Nowadays, there are many different medical treatments to MS, including bariatric surgery, which improves all risk factors. The present study aims to evaluate the influence of gastric bypass in the improvement of risk factors associated with MS, during the postoperative (6 months). This was a retrospective study of 140 patients submitted to gastric bypass. The sample was comprised of a female majority (79.3 %). The mean body mass index (BMI) was 44.17 kg/m2. We evaluated the weight of the subjects, the presence of diabetes mellitus and hypertension as comorbidities, as well as plasma levels of triglycerides (TG), total cholesterol and its fractions, and glycemia, in both preoperative and postoperative. The percentage of excess weight loss (%EWL) was similar in men and women, with an average of 67.82 ± 13.21%. Concerning impaired fasting glucose (≥100 mg/dl), 41 patients (95.3%) presented normal postoperative glycemia. There has been an improvement of every appraised parameter. The mean decrease in TG level was 66.33 mg/dl (p
