Evaluating the Efficacy of the Mediterranean Diet to the Low- Fermentable, Oligosaccharides, Disaccharides, Monosaccharides, and Polyols (FODMAP) Diet in Treating Irritable Bowel Syndrome(IBS)

NCT05807919 | Completed Results

• 2 other identifiers: HUM002274915P30DK089503-13
• Study Type: interventional
• Target: 26
• Locations: 1 country
• Sites: 1

Brief Summary

This study is being completed to determine if the Mediterranean (MD) and low FODMAP (fermentable, oligosaccharides, disaccharides, monosaccharides, and polyols) diets are comparable in the effectiveness to treat Irritable Bowel Syndrome (IBS). The study team hypothesizes that:

• The low FODMAP and Mediterranean groups will achieve a similar improvement in abdominal pain
• Both groups will achieve similar improvements in bloating, overall IBS symptom severity, and adequate relief

Conditions

Irritable Bowel Syndrome

Keywords

Low FODMAP Diet; Mediterranean Diet

Outcome Measures

Primary Outcomes (1)

• Proportion of Participants Who Are Responders Based on the Abdominal Pain Intensity Score for at Least 2 of 4 Weeks

  Results reflect the participants who were weekly responders for at least 2 of the 4 weeks based on their abdominal pain intensity score. The abdominal pain score was a single-question, 11-point numeric rating scale in which 0 represented no abdominal pain and 11 represented the worst possible abdominal pain. Once per day, subjects reported their worst daily (in the past 24 hours) abdominal pain. A weekly responder was defined as a participant whose score decreased in the weekly average of worst abdominal pain in the past 24 hours by at least 30% compared with baseline.

  4 weeks

Secondary Outcomes (5)

• Proportion of Participants Who Are Weekly Responders to Adequate Relief Symptom Assessment for at Least 2 of 4 Weeks

  4 weeks

• Proportion of Participants Who Are Weekly Responders Based on the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version for at Least 2 of the 4 Weeks

  4 weeks

• Change in Mean Score of the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version

  Baseline, 4 weeks

• Proportion of Participants Who Are Weekly Responders to Bloating for at Least 2 of the 4 Weeks

  4 weeks

• Participants Who Are Weekly Responders to Stool Consistency Based on the Bristol Stool Scale (BSS) for at Least 2 of the 4 Weeks

  4 weeks

Study Arms (2)

Diet low in all FODMAP groups

EXPERIMENTAL

Other: Diet low in all FODMAP groups

Diet - Mediterranean

EXPERIMENTAL

Other: Diet - Mediterranean

Interventions

Diet low in all FODMAP groups OTHER

Randomized participants will eat this diet for 4 weeks (all meals and snacks will be provided). Participants will only eat the study food for this intervention. Participants will be asked to complete surveys, food diaries, and have blood and stools samples pre and post treatment.

Diet low in all FODMAP groups

Diet - Mediterranean OTHER

Randomized participants will eat this diet for 4 weeks (all meals and snacks will be provided). Participants will only eat the study food for this intervention. Participants will be asked to complete surveys, food diaries, and have blood and stools samples pre and post treatment.

Diet - Mediterranean

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients with IBS-D (diarrhea-predominant IBS) or IBS-M (IBS with mixed subtype) diagnosed per Rome IV questionnaire and without any unexplained alarm features (rectal bleeding, weight loss, nocturnal symptoms, personal history of celiac disease, microscopic colitis, inflammatory bowel disease)
• Aged 18-70 years at the time of screening
• Weekly average of worst daily (in the past 24 hours) abdominal pain score of ≥3.0 on a 0-to-10-point scale
• At least 80 percent compliance in daily questionnaire entries during the 7-day screening period

You may not qualify if:

• Subjects adhering to any dietary IBS treatment such as the low-fodmap diet, or gluten-free diet, Mediterranean currently or within the past 6 months
• Subjects with a known food allergy to eggs, seafood, peanuts, tree nuts or milk (subjects with lactose intolerance that are experiencing IBS symptoms while on a lactose-free diet will not be excluded from the study).
• Subjects with a history of poorly controlled insulin-dependent or non-insulin-dependent diabetes
• Subjects with a known history of organic Gastrointestinal (GI) disease (i.e., celiac disease, inflammatory bowel disease or microscopic colitis)
• Subjects with a history of an eating disorder requiring medical or behavioral treatment within the past 10 years.
• Subjects with prior small bowel or colonic surgery (excluding appendectomy or cholecystectomy if over 6 months since these 2 procedures)
• Oral antibiotic use in the past 3 months
• Any planned significant changes in dietary or exercise regimen within 30 days prior to Screening or during the study.
• Currently pregnant or breastfeeding.

Sponsors & Collaborators

• University of Michigan: lead
• ModifyHealth: collaborator
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): collaborator

Study Sites (1)

University of Michigan

Ann Arbor, Michigan, 48109, United States

Location

Related Publications (1)

• Singh P, Dean G, Iram S, Peng W, Chey SW, Rifkin S, Lothen-Kline C, Muir J, Lee AA, Eswaran S, Chey WD. Efficacy of Mediterranean Diet vs. Low-FODMAP Diet in Patients With Nonconstipated Irritable Bowel Syndrome: A Pilot Randomized Controlled Trial. Neurogastroenterol Motil. 2025 Oct;37(10):e70060. doi: 10.1111/nmo.70060. Epub 2025 Apr 24.

  PMID: 40273380 DERIVED

MeSH Terms

Conditions

Irritable Bowel Syndrome

Interventions

Diet, Mediterranean

Condition Hierarchy (Ancestors)

Colonic Diseases, Functional; Colonic Diseases; Intestinal Diseases; Gastrointestinal Diseases; Digestive System Diseases

Intervention Hierarchy (Ancestors)

Diet, Plant-Based; Diet Therapy; Nutrition Therapy; Therapeutics; Diet; Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Results Point of Contact

• Title: Prashant Singh
• Organization: University of Mihcigan

singhpr@med.umich.edu

734-647-9252

Study Officials

• Prashant Singh, MD

  University of Michigan

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: Participant and investigators will not know what study cohort participants have been randomized into.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor of Internal Medicine

Model Details: Subjects meeting all eligibility criteria will be randomized in a 1:1 ratio to receive either the MD or the LFD for a four-week period.

Study Record Dates

• First Submitted: March 29, 2023
• First Posted: April 11, 2023
• Study Start: April 10, 2023
• Primary Completion: November 3, 2023
• Study Completion: November 3, 2023
• Last Updated: March 28, 2025
• Results First Posted: March 28, 2025

Record last verified: 2025-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)