Effects of VLCD and Bariatric Surgery in Patients With Type 2 Diabetes

The investigators are therefore interested to explore the effects of VLCD and different bariatric surgery procedures to changes in the physical deposition of fat in organs which regulate glucose metabolism (i.e. in the liver, pancreas, muscle) in the earlier (6 weeks) and intermediate (4 months) period after bariatric surgery, where rate of weight loss at this stage are similar between the two procedures. Increased understanding of the changes in these important metabolic organs, will increase the investigators' understanding of mechanism of diabetes remission following bariatric surgery, their effects on weight loss or changes in gut hormones levels. Magnetic Resonance imaging (MRI) and Magnetic Resonance spectroscopy (MRS) are non-invasive, non-ionising techniques. MRI can be used to investigate the body's physiology and MRS can be used to investigate the body's metabolic processes, so by combining these two methods the investigators are able to investigate the process of fat reduction and diabetes remission post gastric surgery without performing any secondary invasive procedures The purpose of this project is to investigate the effects of a Very Low Calorie Diet (VLCD) followed by two different bariatric surgical procedures, Roux-en-Y Gastric Bypass (RYGB) and Sleeve gastrectomy (SG) on skeletal muscle, liver and pancreatic fat deposition, ATP flux as well as cardiac function.