Gut Microbiota Post Roux-en-Y Gastric Bypass Surgery

Inclusion Criteria:

• Female
• Age 18-65
• 3-5 years post Roux-en-Y gastric bypass and experienced successful weight loss following surgery (up to n=10) or
• 3-5 years post Roux-en-Y gastric bypass and did not experience optimal weight loss following surgery (up to n=10) or
• Nonsurgical control participants who are approximately matched in sex, age, and BMI to the optimal weight loss group (up to n=10).

Exclusion Criteria:

• Tobacco use in past three months.
• Taking a medication which is known to significantly influence gastrointestinal transit time or affect the microbiome or other variables significantly (as determined by study pharmacist/MD).
• History of diabetes mellitus.
• Has taken an oral or IV/IM antibiotic in the past 3 months.
• Has taken probiotic and/or prebiotic agent in the past 3 months
• History of significant intestinal disease or disorder (e.g., Crohn's disease, ulcerative colitis, irritable bowel syndrome)
• History of gastrointestinal surgery that may impact measures of biological variables, as determined by the investigator.
• Medical condition expected to impact the biological variables of interest or interfere with providing a sample, as determined by the investigator.
• Unable to speak/read English.
• Breastfeeding, pregnant, or planning to become pregnant within the duration of the study.
• Unwilling to use a medically acceptable form of contraception.
• History of bipolar or psychotic spectrum disorder or alcohol or substance treatment in the past year