Biomarkers of Diet-microbiota Interactions in Irritable Bowel Syndrome

Biomarkers of Diet-microbiota Interactions in Irritable Bowel Syndrome

Most patients suffering from the irritable bowel syndrome (IBS) report that ingestion of certain foods is a major trigger of symptoms, but the reason is unclear. Previous studies have shown that foods containing poorly absorbed carbohydrates (FODMAPs) are fermented by the bacteria in our bowels and these cause symptoms in some but not all patients. Gut bacteria are capable of producing various products, such as neuroimmune mediator histamine, that may be related to IBS symptoms. Our recent data suggest that consumption of FODMAPs promotes production of bacterial histamine.

The main objective of this study is to investigate bacterial production of histamine and its relationship to IBS symptoms. The study will involve 6 weeks on a low-FODMAP diet with three three-day interventions consisting of High- or Low-FODMAP drinks along with probiotics or placebo capsules. The patient's bacteria and metabolites will be analyzed at various time points.

Inclusion Criteria:

• Adults aged 18-75 with IBS (Rome IV criteria) who have self-reported previous improvement in their IBS symptoms while on a low FODMAP diet, or when excluding certain high-FODMAP foods, or patients in whom histamine is expected to play a key role (either diagnosed with high histamine producing bacteria, or improved IBS symptoms after using antihistamines). Individuals should be able to swallow size 00 capsules.

Exclusion Criteria:

• Concurrent significant organic GI pathology (i.e. celiac, IBD, etc.)
• Concurrent systemic disease (such as diabetes) and/or laboratory abnormalities considered by investigators to be risky or that could interfere with data collection
• History of active cancer in the last 5 years, other than basal cell cancer
• Pregnant or breastfeeding women
• Active or recent participation (< 1 month) in a clinical study, except for SPOR IMAGINE
• Use of antibiotics, probiotics, or ACE inhibitors during, or one month prior to the study
• Use of new medications less than 4 weeks prior to the study.
• Allergies to any of the ingredients used in the study
• Any immune-compromising conditions