Effect of a Low FODMAP Diet on SIBO Breath Test Positivity

NCT04627727 | Terminated Early Phase 1 Results

• 1 other identifier: 2020P000622
• Study Type: interventional
• Target: 14
• Locations: 1 country
• Sites: 1

Brief Summary

Bloating is the most common symptom associated with disorders of brain-gut interaction (i.e., functional bowel disorders) such as irritable bowel syndrome, a disorder characterized by abdominal pain and altered bowel habits which affects up to 11% of world population. A common cause of bloating is small intestinal bacterial overgrowth (SIBO), a condition defined by excessive and/or abnormal type of bacteria in the small bowel. The potential role of SIBO for irritable bowel syndrome (IBS) was initially proposed by Pimentel et al. Using lactulose breath tests (LBTs), 78% of patients with IBS were also diagnosed with SIBO. After antibiotic therapy, 48% of patients no longer met the Rome criteria for IBS. A recent systematic review and meta-analysis concluded that the prevalence of SIBO is increased in IBS.

Conditions

SIBO

Outcome Measures

Primary Outcomes (1)

• SIBO Diagnosis

  Number of Participants with Negative and Positive SIBO

  four weeks

Study Arms (1)

low FODMAP diet

EXPERIMENTAL

Consenting patients fulfilling the inclusion and exclusion criteria will undergo a 7-day screening period to assess baseline symptoms and then go on a 4-week low FODMAP diet

Other: low FODMAP diet

Interventions

low FODMAP diet OTHER

low FODMAP diet

low FODMAP diet

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Aged 18-65 years at the time of screening
• Meet Rome IV criteria for functional bloating
• IBS-SSS score of at 176 (0-500)
• SIBO positive

You may not qualify if:

• individuals already on a LFD or other dietary restriction such as gluten free diet within the past 6 months
• individuals with peanut, soy, or seafood allergies or insulin-dependent diabetes
• known history of celiac disease, inflammatory bowel disease or microscopic colitis
• prior small bowel or colonic surgery or cholecystectomy
• pregnant patients
• antibiotics, excluding topical, in the past 3 months

Sponsors & Collaborators

• Beth Israel Deaconess Medical Center: lead

Study Sites (1)

Beth Israel Deaconess Medical Center

Boston, Massachusetts, 02215, United States

Location

Related Publications (1)

• Lemos MPC, Zucoloto TG, Oliveira MC, de Oliveira GLV. Dysbiosis and Gut Microbiota Modulation in Systemic Sclerosis. J Clin Rheumatol. 2022 Mar 1;28(2):e568-e573. doi: 10.1097/RHU.0000000000001748.

  PMID: 34030162 DERIVED

MeSH Terms

Interventions

FODMAP Diet

Intervention Hierarchy (Ancestors)

Elimination Diets; Diet; Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Limitations and Caveats

Early termination leading to small numbers of subjects analyzed

Results Point of Contact

• Title: Judy Nee, mD
• Organization: BIDMC

jnee@bidmc.harvard.edu

617-667-2193

Study Officials

• Anthony Lembo, M.D

  Beth Israel Deaconess Medical Center

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor of Medicine

Study Record Dates

• First Submitted: October 30, 2020
• First Posted: November 13, 2020
• Study Start: November 15, 2020
• Primary Completion: December 15, 2024
• Study Completion: December 15, 2024
• Last Updated: July 4, 2025
• Results First Posted: July 4, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)