Clinical Trials

Inclusion Criteria

• Individuals aged 20-65 years
• Seen for weight management in the Nutrition Clinic at the Mayo Clinic
• Recruited prior to undergoing Roux-en-Y Gastric Bypass surgery
• Have a fasting glucose concentration of ≥ 126 mg/dl on two or more occasions
• Or  have a history of type 2 diabetes or impaired fasting glucose treated with one or two oral agents other than thiazolidinediones
• Control group with type 2 diabetes or impaired fasting glucose who are not interested in pursuing surgical intervention but are willing to undergo supervised caloric restriction 
  • The 2 groups will be matched for age, gender, BMI and the duration and severity (HbA1c and number of oral medications needed to achieve glycemic control) of diabetes

Exclusion Criteria

• Subjects < 20 years of age will not be studied to minimize the possibility of type 1 diabetes
• Subjects > 65 years of age will not be studied to minimize the potential confounding effects of age on glucose tolerance
• Subjects on chronic antibiotic therapy will be excluded due to their influence on gut bacteria
  • Subjects will refrain from using antibiotics for 2 weeks prior to the screening visit until completion of the study, except for routine peri-operative use and as clinically indicated
• Healthy status will indicate that the participant has no known active systemic illness and no active microvascular or macrovascular complications of their diabetes