 We will longitudinally phenotype 130 obese diabetics undergoing Roux-en-Y Gastric Bypass or Sleeve Gastrectomy surgery. Patients will be assessed preoperatively and at 3 months and 1 year postoperatively. The primary clinical outcome will be diabetes remission. Other clinical measures recorded will include; 1 anthropometric physiological measurements, 2 demographic details, 3 biochemical parameters, 4 anti-hyperglycaemic and other medication use, 5 co-morbidity status and 6 dietary choices through 24hr dietary recall questionnaires. 