Inclusion Criteria:  Be approved and scheduled for metabolic surgery at the Vanderbilt University Medical Center Have a history of type 2 diabetes, hypertension, or dyslipidemia Be able and willing to provide personal information and biological samples needed for the study  Exclusion Criteria:  Prior gastric operations A history of coronary artery disease, stroke, heart failure, HIV infection, or untreated viral hepatitis Chemotherapy or radiotherapy for cancer within 2 years Current inflammatory bowel disease or celiac disease Vomiting, constipation, or diarrhea within 7 days or use of antibiotics within 2 months