Background Among the restrictive procedures the role of restrictive vs. resecting the stomach is still ambiguous. This study evaluate which is the role of the stomach with respect to blood glucose levels (BG) and percent excess weight loss (EWL) over the 18 months after restrictive procedures in morbid obese diabetic patients. Methods We retrospectively compared a group of patients who underwent partial gastrectomy (just part of the gastric body) with gastric banding (GBSR; n = 27), sleeve gastrectomy (part of gastric body and complete fundus resection; LSG; n = 53) to laparoscopic gastric banding (LAGB; n = 100). Differences among groups at 3, 6, 12, and 18 months were evaluated by analysis of variance. The three cohorts were diabetic patients similar in BMI, age, and gender. Results At 12 and 18 months, LSG had higher EWL ( P < 0.05) and lower BG ( P < 0.05) than did either LAGB or GBSR. There were no operative deaths. Complications: LAGB—two staple-line oozing, two wound infections; LSG—one hemorrhage, two staple-line oozing, two leaks; GBSR—one hemorrhage, two wound infections. All complications were readily treated. Conclusions LSG provides better weight loss and glucose control at 1 year and 1.5 years after surgery than does either LAGB or GBSR, suggesting that gastric fundus resection plays an important, not yet well-defined, role.