The Effect of a Gastric Bypass on Type 2 Diabetes in the Morbidly Obese Patient

Inclusion Criteria: * Female or male subjects aged 18 to 65 * BMI \> 35 kg/m2 * Subject is capable and willing to give informed consent. * In the surgical groups indication for surgery is approved by the local multidisciplinary obesity workgroup following the NIH guidelines of 199112. * Patient suffers from type 2 diabetes necessitating insulin therapy. * Subject is a non-smoker for at least 6 months prior to study start. * Female patients of child bearing potential must use oral, injected or implanted hormonal methods of contraception from at least the commencement of their last normal period prior to the screening visit. Patients using hormonal contraception should use a barrier method in addition from screening visit until their next normal period following the end of the study. * Female patients of non-child bearing potential defined as: * Post-menopausal females, being amenorrhoeic for at least 1 year * Pre-menopausal females with a documented hysterectomy or bilateral oophorectomy. Exclusion Criteria: * Female patient is pregnant or breastfeeding. * BMI \< 35 kg/m2 * Patient suffers from an endocrine disease, besides diabetes and thyroid disease, such as Cushing's disease, Addison's disease, hypothalamic tumor…) * Patient suffers from type 1 diabetes, MODY or LADA * Patient has undergone previous surgical procedure for weight loss * Patient is considered ASA 4 or more according to the ASA physical status classification system of the American Society of Anesthesiologists. * Patient suffers from liver cirrhosis * Patient uses steroids * Patient uses cyclosporin * Recent (\<30 days) or simultaneous participation in another clinical trial. * Any situation that can compromise the study, including serious illness or a predictable lack of cooperation from the subject.