Patient description: The patient is a 34-year-old obese woman who comes to the clinic with weight concerns. She is 165 cm tall, and her weight is 113 kg (BMI: 41.5). In the past, she unsuccessfully used antiobesity agents and appetite suppressants. She is complaining of sleep apnea, PCO and dissatisfaction with her body shape. She is a high-school teacher. She is married for 5 years. She doesn't use any contraceptive methods for the past 4 months and she had no prior pregnancies. She rarely exercises and movement seems to be hard for her. She is not able to complete the four-square step test in less than 15 seconds. She does not smoke or use any drugs. Her BP: 130/80, HR: 195/min and her BMI is: 41.54. Her lab results: FBS: 98 mg/dl TG: 150 mg/dl Cholesterol: 180 mg/dl LDL: 90 mg/dl HDL: 35 mg/dl She is considering a laparoscopic gastric bypass.

Clinical trial eligibility criteria: eligible ages (years): 18.0-70.0,  Obesity Diabetes Mellitus, Type 2 NAFLD Be an eligible candidate for bariatric surgery based on standard in place, have been enrolled in bariatric surgery program at Cleveland Clinic Main Campus, and have been cleared and approved for bariatric surgery by the BMI bariatric program and his/her health insurance Have a Body Mass Index (BMI) more than 35 kg/m2 Have type 2 diabetes (T2D) (but not type 1 diabetes, see  ) as defined by 1. If untreated (as per ADA standards of care) FPG > or = 126 mg/dL (7.0 mmol/L). Fasting is defined as no caloric intake for at least 8 h OR 2-h PG > or = 200 mg/dL (11.1 mmol/L) during OGTT. The test should be performed as described by the WHO, using a glucose load containing the equivalent of 75-g anhydrous glucose dissolved in water OR A1C > or = 6.5% (48 mmol/mol). The test should be performed in a laboratory using a method that is NGSP certified and standardized to the DCCT assay OR In a patient with classic symptoms of hyperglycemia or hyperglycemic crisis, a random plasma glucose > or = 200 mg/dL (11.1 mmol/L). 2. the use of any antidiabetic drug or glucose lowering agent, including biguanides (metformin), thiazolidinediones, alpha-glucosidase inhibitors, sulfonylurea, meglitinides, DPP4-inhibitors, GLP1-agonists, SGLT2i, any type of insulin Have the ability and willingness to participate in the study and agree to the study terms As a standard of care, have a negative urine pregnancy test prior to surgery for women of childbearing potential. A woman of childbearing potential is one who is biologically capable of becoming pregnant. This includes women who are using contraceptives or whose sexual partners are either sterile or using contraceptives Any contra-indication for bariatric surgery (standard of care) Lack of insurance coverage for bariatric surgery Diabetes mellitus other than T2D including Type 1 diabetes or Latent Autoimmune Diabetes of the Adult (LADA) as defined by personal history of diabetic ketoacidosis or by positive auto-antibodies to glutamic Acid Decarboxylase (GAD-65), Islet Cell Antibodies (ICA), Insulin Autoantibodies (IAA), or to protein tyrosine phosphatase (IA-2A) Monogenetic or neonatal diabetes Prior bariatric surgery of any kind Known history of chronic liver disease except for NAFLD/NASH: hepatitis, positive serologic test result for hepatitis B surface antigen and/or hepatitis C antibody, alpha-1-antitrypsin deficiency Known Gastrointestinal disorders including a known history of celiac disease and/or any other malabsorptive disorders or inflammatory bowel disease (Crohn's disease or ulcerative colitis) Psychiatric disorders including dementia, active psychosis, severe depression requiring > 2 medications, history of suicide attempts, alcohol or drug abuse within the previous 12 months