A Dietary Intervention Study on the Microbiome in Crohn's Disease Patients

Study Purpose

This protocol is designed to compare the effectiveness of a soy-based diet or identical diet without soy given to patients with Crohn's disease (CD) in remission, patients with active CD, or healthy controls. The assigned diet will be compared to participant 'baseline' (pre-diet) in terms of its ability to change the gut bacteria and fecal butyrate, an important short-chain fatty acid (SCFA) that limits bowel inflammation, a characteristic of this debilitating disease.

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.

Searching Both is inclusive of interventional and observational studies.

Eligible Ages 18 Years - 65 Years
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - CD subjects: Documented diagnosis of Crohn's disease.
Control subjects: no documented diagnosis of CD.
  • - CD subjects: Harvey Bradshaw Index (HBI) score <4 ('CD remission'), or with HBI score >8 ('CD moderate disease') - Capable of providing consent to participate.
  • - Access to technology that permits the daily completion of study related activities.
  • - Able to receive and have an adult sign for food shipments delivered to a work or home environment.
  • - Negative pregnancy test at screening visit in females of childbearing potential.
  • - Able to take oral nutrition and medication intake for 3 months prior to and at time of study enrolment.
  • - 'CD remission' subjects: No change in 'IBD related' medications within 8 weeks prior to normally scheduled appointment with treating gastroenterologist (pre-screening): biologics, immunosuppressants, corticosteroids.

Exclusion Criteria:

  • - Short bowel syndrome.
  • - Hospitalized patients.
  • - Body mass Index <19 kg/m or ≥35.
  • - Known clinically significant liver/gallbladder/pancreatic disease/dysfunction.
  • - Individuals who lack consent capacity, including the mentally ill, prisoners, cognitively impaired participants, dementia patients.
  • - Uncontrolled Diabetes Type I type II.
  • - Known drug abuse.
  • - Known parasitic disease of the digestive system.
symptomatic intestinal stricture.
  • - Presence of an ostomy.
  • - Known concurrent malignancy.
  • - Other conditions that would be a contraindication to and of the study diets (e.g. Soy, peanut, wheat, gluten allergy.
) or preclude the participant from completing the study.
  • - Start of new 'IBD related' medications within 8 weeks prior to enrollment: biologics, immunosuppressants, corticosteroids.
  • - Documented C difficile colitis within four weeks of screening.
  • - Well-founded doubt about the patient's cooperation.
  • - Existing pregnancy or lactation.
  • - Current participation in another diet intervention, simultaneous participation in another clinical trial, or participation in any other dietary intervention trial within the last 30 days.
  • - History of <3 natural bowel movements per week.
  • - Unable to access to technology that permits the daily completion of study related activities.
- Currently consuming a soy-based diet

Trial Details

Trial ID:

This trial id was obtained from ClinicalTrials.gov, a service of the U.S. National Institutes of Health, providing information on publicly and privately supported clinical studies of human participants with locations in all 50 States and in 196 countries.


Phase 1: Studies that emphasize safety and how the drug is metabolized and excreted in humans.

Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

Phase 4: Studies occurring after FDA has approved a drug for marketing, efficacy, or optimal use.

Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

Case Western Reserve University
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

Fabio Cominelli, MD, PhD
Principal Investigator Affiliation Case Western Reserve University, School of Medicine, Gastroenterology
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Other, NIH
Overall Status Recruiting
Countries United States

The disease, disorder, syndrome, illness, or injury that is being studied.

Crohn Disease
Additional Details

The inflammatory bowel disease (IBD) subtype, Crohn's disease (CD) is a chronic and relapsing inflammatory disorder of the gastrointestinal tract. Although the precise etiology of IBD is not known, evidence suggests that environmental factors, including diet, contribute to its pathogenesis. A soy-based diet has been demonstrated to have numerous health benefits. This single-center open-label study will compare the effectiveness of a soy-based diet or an identical diet without soy to change the gut microbiota composition and fecal butyrate concentration to that of baseline (pre-diet) in patients with CD (remission or active disease) and healthy control subjects without CD. Participants will follow either a soy-based diet or an identical diet without soy to which they will be randomized for 7 days. No data collection or other study procedures will take place until the potential participant provides written informed consent to participate in the research study. The informed consent, screening, enrollment, and baseline data collection which make up visit 1 can occur on the same day or be completed across several days.

Arms & Interventions


Experimental: Soy-based diet

Participants will be randomized to follow a soy-based diet for 7 days. The diet will be preceded by a 12-hr overnight fast.

Active Comparator: Regular diet

Participants will be randomized to follow a diet without soy for 7 days. The diet will be preceded by a 12-hr overnight fast.


Other: - Soy based diet

The diet will be based on the detailed descriptions according to the American Heart Association, US Food and Drug Administration (FDA), and the Soyfoods Association of North America Website, which all promote soy products as having beneficial nutrient profiles with a daily consumption of 25 grams or more of soy protein (average serving = 6.25 grams), upper limit of 50g.

Other: - Non-soy based diet

Diet of identical composition to the soy diet with the exception of soy.

Contact a Trial Team

If you are interested in learning more about this trial, find the trial site nearest to your location and contact the site coordinator via email or phone. We also strongly recommend that you consult with your healthcare provider about the trials that may interest you and refer to our terms of service below.

Cleveland, Ohio




University Hospitals Digestive Health Institute

Cleveland, Ohio, 44106

Site Contact

Tracy Krebs, BS