Vegetarian Diet in Ulcerative Colitis

Study Purpose

To determine whether a lacto-ovo vegetarian diet is effective in improving gastrointestinal symptoms, quality-of-life, intestinal inflammation and gut microbiota composition in mild-to-moderate UC compared to a standard omnivorous diet.

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 - 79 Years
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - I.
Is able to provide informed consent.
  • II. Is over the age of 18 years.
  • III. Has a diagnosis of ulcerative colitis for over a 3-month duration that was confirmed by a specialist gastroenterologist with a MAYO score up to 9.
  • IV. Medications: 1.
Oral 5-Aminosalicylates: If taking an oral 5-Aminosalicylates the patient has used them continuously for 4 weeks and has been on a stable dose for 2 weeks prior to the screening visit. 2. Oral Corticosteroids: If taking oral corticosteroids the patient has used them continuously for 4 weeks and has been on a stable dose for 2 weeks prior to the screening visit at a dose of ≤30mg. 3. Oral Azathioprine/6MP, Methotrexate or tacrolimus: If taking one of these medications the patient has used them for a minimum of 12 weeks and has been on a stable dose for 4 weeks prior to screening. 4. Biologic therapy with infliximab, adalimumab or vedolizumab: If taking one of these medications the patient has used them for a minimum of 12 weeks 5. Rectal Preparations; 5-Aminosalicylates, corticosteroids or tacrolimus: If taking one of these medications the patient has used them continuously for 4 weeks and has been on a stable dose for 2 weeks prior to the screening visit.
  • V. Willing to participate in the study and comply with the proceedings by signing a written informed consent.
  • VI. Free of any clinically significant disease, other than ulcerative colitis, that would interfere with the study's evaluations.
  • VII. Subjects can read and understand English and is able to adhere to the study methodology and visit schedules.

Exclusion Criteria:

  • - I.
Has Crohn's disease.
  • II. Has been on antibiotics within the last four weeks.
  • III. Has a known food allergy to nuts, soy, eggs or dairy.
  • IV. Is pregnant or breast feeding.
  • V. Following a vegetarian, vegan or low FODMAP diet.
  • VI. Has known dementia and the inability to understand the trial requirements.

Trial Details

Trial ID:

This trial id was obtained from, 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.

Edith Cowan University
Principal Investigator

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

Principal Investigator Affiliation N/A
Agency Class

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

Overall Status Recruiting
Countries Australia

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

Ulcerative Colitis
Additional Details

This study will review whether a lacto-ovo vegetarian diet is an optimal dietary therapy to achieve a clinical response in mild to moderate UC as an adjunctive treatment to current medical therapies. The proposed RCT will be used to evaluate the efficacy of a lacto-ovo vegetarian diet together with its effect on the microbiota to create an enhanced understanding of the role diet plays in the management of UC. Using a socially acceptable diet it is anticipated that food-related quality-of-life measures will improve for participants. Dietary modification could be a more economical, safer and more effective means of reducing symptoms and flare-ups compared to pharmacological therapy.

Arms & Interventions


No Intervention: Control Group

Patients will be asked to continue their usual diet patterns over an 8 week period

Experimental: Intervention Group

Patients will follow a lacto-ovo vegetarian diet for an 8 week period. patients will be provided with a lacto-ovo vegetarian food box delivery service with fresh ingredients and recipes to cover four dinners per week.


Other: - Lacto-ovo vegetarian diet

Lacto-ovo vegetarian diet inclusive of dairy and eggs

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.

International Sites

St John of God Subiaco Hospital, Perth, Western Australia, Australia




St John of God Subiaco Hospital

Perth, Western Australia, 6111

Site Contact

Charlene Grosse


The content provided on clinical trials is for informational purposes only and is not a substitute for medical consultation with your healthcare provider. We do not recommend or endorse any specific study and you are advised to discuss the information shown with your healthcare provider. While we believe the information presented on this website to be accurate at the time of writing, we do not guarantee that its contents are correct, complete, or applicable to any particular individual situation. We strongly encourage individuals to seek out appropriate medical advice and treatment from their physicians. We cannot guarantee the availability of any clinical trial listed and will not be responsible if you are considered ineligible to participate in a given clinical trial. We are also not liable for any injury arising as a result of participation. For a full description of terms please refer to our Terms, Conditions & Privacy.