Objectives: To determine the effects imposed by laparoscopic sleeve gastrectomy (LSG) on obesity-associated  co-morbidities. Patients & methods: The study included 40 patients; 13 morbid obese and 27 obese patients. All patients  were evaluated  preoperatively for existence  and severity  of co-morbidities and determination of Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). All patients underwent LSG; operative time, hospital  stay, and intraoperative and postoperative (PO) complications were registered. Postoperative monitoring included evaluation of the percentage of excess weight loss (roEWL)and the percentage of excess body mass index loss (roEBMIL) at 3, 6, 12 and 24 months after surgery; the frequency of associated co-morbidities and HOMA­ IR index was evaluated at 6, 12 and 24 months after surgery. Results: Mean operative time was 157.8±17 minutes and mean duration of hospital stay was 5.5±0.9 days. No conversion to open surgery.  All patients  showed  progressive weight  loss throughout the follow-up period with progressively increasing roEWL and roEBMIL. BMI strata showed significant progressive change throughout follow-up period; 27 women were overweight and only 13 women were obese. All obesity-associated co-morbidities showed  progressive improvement  or resolution. At end of follow-up,  7 patients still had co-morbidities, 9 patients had improved co-morbidities and 24 patients had resolved co-morbidities with an improvement and resolution rates of22.5% and 60%, respectively and only 11 co-morbidities were recorded at end of follow-up in various combinations in the 7 non-responders. Preoperatively, all patients were insulin resistant; however, at the end of follow-up period HOMA-IR index of all patients was within the non-resistant range. Conclusion:  Bariatric surgery effectively  improves  obesity-associated co-morbidities  and could be considered  as non-pharmacological therapeutic  modality for these co-morbidities. Laparoscopic gastric sleeve is a safe and effective appropriate surgical procedure for morbidly obese patients with associated co-morbidities.