Background: Laparoscopic sleeve gastrectomy (LSG) for morbid obesity is gaining in popularity as it offers several advantages over laparoscopic Roux-en-Y gastric bypass (LRYGBP), but comparative data between these two procedures have rarely been reported. Methods: This case control study compared the incidence of low-grade systemic inflammation, insulin resistance, anthropometrics, resting energy expenditure and metabolic syndrome in 30 patients undergoing LRYGBP and 30 patients undergoing LSG, matched for age, sex, body mass index (BMI), and glycosylated hemoglobin (HbA1c). Results: At 1-year after surgery, the percent of excess weight loss was 67.8 +/- 20.9 for LRYGBP and 61.6 +/- 19.4 for LSG. Patients undergoing LRYGBP showed significantly lower plasma levels of C-reactive protein (3.3 +/- 2.7 mg/dL vs. 5.3 +/- 3.9 mg/dL; P < 0.05), waist circumference (97.4 +/- 16.0 vs. 105.5 +/- 14.7 cm; P < 0.05), total cholesterol (4.6 +/- 1.0 vs. 5.7 +/- 0.9 mmol/L; P < 0.01) and LDL cholesterol (2.6 +/- 0.8 vs. 3.6 +/- 0.8 mmol/L; P < 0.01). Insulin resistance (HOMA index 1.6 +/- 1.0 after LRYGBP vs. 2.3 +/- 2.4 after LSG), resting energy expenditure (1666.7 +/- 320.5 after LRYGBP vs. 1600.4 +/- 427.3 Kcal after LSG) and remission of metabolic syndrome (92.9% after LRYGBP vs. 80% after LSG) were not different between the two groups. Conclusion: In this study, patients undergoing LRYGBP demonstrated significantly improved lipid profiles, decreased systemic low-grade inflammation compared with those undergoing LSG at 1-year follow-up. (C) 2013 Published by Elsevier Masson SAS.