Fecal bile acids, fecal short chain fatty acids and the intestinal microbiota in patients with irritable bowel syndrome (IBS) and control volunteers: Diet Challenge

Patients with IBS and asymptomatic controls (healthy volunteers) with no prior history of GI disease or symptoms.

Participants should be on a stable and consistent diet regimen and should not be following an extreme diet intervention such as gluten-free or a low fermentable oligo-, di-, monosaccharides, and polyols diet (FODMAP) diet at the time of study participation.

Participants with microscopic/lymphocytic/collagenous colitis, inflammatory bowel disease, celiac disease, visceral cancer, chronic infectious disease, immunodeficiency, uncontrolled thyroid disease, history of liver disease

Prior radiation therapy of the abdomen or abdominal surgeries with the exception of appendectomy or cholecystectomy > 6 months prior to study initiation

Ingestion of any prescription, over the counter, or herbal medications which can affect GI transit or study interpretation (e.g. opioids, narcotics, anticholinergics, norepinephrine reuptake inhibitors, nonsteroidal anti-inflammatory drugs, COX-2 inhibitors, bile acid sequestrants) within 6 months of study initiation for asymptomatic volunteers or within 2 days before study initiation for IBS patients. Stable low doses of tricyclic antidepressants or serotonin reuptake inhibitors will be permitted for individuals who have been taking them for a period of greater than one month. Rescue therapy to facilitate stool collection will be permitted where needed.

Any females who are pregnant or breast-feeding

Antibiotic usage within 3 months prior to study participation

Prebiotic or probiotic usage within the 2 weeks prior to study initiation

Use of tobacco products within the past 6 months.