title: Gastric bypass and diabetes: past, present and future.
abstract: BACKGROUND
  Owing to the pathogenic role of insulin resistance and beta-cell dysfunction in type 2 diabetes, the clinical manifestation of this disease is extremely complex and is often associated with obesity. In recent years, Roux-en-Y gastric bypass (RYGB) surgery, which was originally developed to treat morbid obesity, has been found to have therapeutic potential for diabetes. However, the underlying mechanisms of the therapeutic application of this technique are not fully known.
  
  
  OBJECTIVE
  This review describes the technique of RYGB, including the advantages and disadvantages of the procedure. The advantages include metabolic improvement, obesity resolution, and reduction in morbidity. The disadvantages include short-term perioperative complications and long-term nutritional disorders. Finally, we provide a review of the possible underlying mechanisms leading to the resolution of type 2 diabetes symptoms after the RYGB procedure.
  
  
  CONCLUSIONS
  While some complications are found after RYGB, there have also been reports showing a remarkable decrease in mortality, successful weight loss, and resolution of type 2 diabetes. The actual mechanism leading to diabetes resolution remains unknown. Gastric bypass surgery is certainly an effective method to increase remission rate in a subgroup of type 2 diabetes patients with morbid obesity.
authors.affiliation: Department of Medicine, College of Medicine, National Taiwan University Hospital, Taipei.
authors.forename: Tse-I
authors.initials: TI
authors.lastname: Lee
authors.forename: Jui-Hung
authors.initials: JH
authors.lastname: Chen
authors.forename: Ting-Chia
authors.initials: TC
authors.lastname: Weng
authors.forename: Keong
authors.initials: K
authors.lastname: Chong
authors.forename: Wei-Jei
authors.initials: WJ
authors.lastname: Lee
authors.forename: Lee-Ming
authors.initials: LM
authors.lastname: Chuang
mesh_terms: D003924:Diabetes Mellitus, Type 2 / Q000209:etiology / Q000378:metabolism / Q000601:surgery*; D015390:Gastric Bypass / Q000009:adverse effects / Q000379:methods; D006801:Humans; D007333:Insulin Resistance; D009767:Obesity, Morbid / Q000150:complications / Q000378:metabolism / Q000601:surgery*; D016896:Treatment Outcome; D015431:Weight Loss