Recruiting

Mediterranean Diet

Sponsor:

The Hospital for Sick Children

Code:

NCT06474546

Conditions

Arthritis, Juvenile

Arthritis, Childhood

Juvenile Idiopathic Arthritis

Eligibility Criteria

Sex: All

Age: 8 - 18

Healthy Volunteers: Not accepted

Interventions

Diet intervention

Study Details

Brief summary:

Families of children with arthritis are highly interested in the benefits of diet to improve their child's disease and future health outcomes. Previous research shows that the germs - bacteria and other organisms - that live in the intestines (gut microbiome) are important to how well immune systems work, and that what people eat changes their gut microbiome. The investigators want to study whether a certain diet - based on the principles of the Mediterranean Diet - will improve arthritis for children and whether it was changes in the microbiome that led to improvement.

Fifty-four participants in this study will change their diet for an 8-week period, and will have the option of remaining on the diet for an additional 4 weeks. At three time points during the study (beginning, 8 weeks, and 12 weeks), participants will provide stool and blood samples, will complete questionnaires about diet and other aspects of lifestyle and health, and will complete a disease assessment by a clinician. From collecting all these samples and information, the investigators will be able to determine if the diet was successful in improving disease activity in children with arthritis and if the gut microbiome was changed as well.

This study will help the investigators figure out if a larger, and more definitive, study like this is possible to do in children with arthritis and will help the investigators design a bigger multinational study to confirm how diet affects disease outcomes and the microbiome in children with arthritis. If successful, this research will provide scientific knowledge to help families make their way through this difficult to- navigate topic.

Conditions

Arthritis, Juvenile

Arthritis, Childhood

Juvenile Idiopathic Arthritis

Study ID

NCT06474546

Start date

Apr 7, 2025

Status verified date

Jul, 2026

Completion date

Oct, 2028

Anticipated

Primary completion date

Aug, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 8 - 18

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Ages 8-18 years
  • Diagnosis of JIA (excluding systemic JIA, enthesitis-related arthritis, and rheumatoid factor (RF) positive polyarthritis) as per International League of Associations for Rheumatology (ILAR) criteria. (For this feasibility study, there will be no requirement for any particular level of disease activity.)
  • Subjects on stable treatment - i.e., any medical treatment with disease-modifying antirheumatic drugs (DMARDs) and/or systemic or intraarticular corticosteroids, has been unchanged for 8 weeks, and is unlikely to change for 12 weeks as judged by the treating physician.
  • Willingness to provide stool samples.
  • English or French fluency adequate to answer the study questionnaires, and participate in diet instruction, as judged by the enrolling physician.

Exclusion Criteria:

  • Documented specific food allergies, celiac disease.
  • Co-morbidities that might impact the tolerability of the study diet, e.g., type I diabetes, peptic ulcer disease, etc.

Study Design

Enrollment

54 participants

Anticipated

Intervention Model

Single group

Primary purpose

Supportive Care

Interventions and Outcome Measures

Arms

experimental: Intervention

Diet (MedDiet)

Interventions

Diet intervention

A diet based on the principles of the Mediterranean Diet (MedDiet): consists of an abundance of plant foods - unrefined cereals, fruit, vegetables, and extra-virgin olive oil - a moderate consumption of poultry, dairy products, eggs, and low consumption of sweets and red meats.

All subjects will be instructed to follow the MedDiet for 8 weeks by the study team. Families will be given the option to continue for 12 weeks if they wish to do so.

Primary outcome measure

  • (Feasibility 1) Participant accrual rate: [ Time Frame: 8-12 weeks ]
  • (Feasibility 2) The proportion of subjects who complete all the various measurement steps [ Time Frame: 8-12 weeks ]
  • (Feasibility 3) Nutrient intake [ Time Frame: 8-12 weeks ]
  • (Feasibility 4) Adherence to the MedDiet [ Time Frame: 8-12 weeks ]
  • (Feasibility 5) Tolerability of diet intervention [ Time Frame: 8-12 weeks ]
  • (Mediator 1) Changes in the microbiome [ Time Frame: 8-12 weeks ]
  • (Mediator 2) Changes in juvenile arthritis disease activity score [ Time Frame: 8-12 weeks ]
  • (Mediator 3) Changes in functional status [ Time Frame: 8-12 weeks ]
  • (Mediator 4) Changes in quality of life [ Time Frame: 8-12 weeks ]
  • (Mediator 5) Changes in gut inflammation [ Time Frame: 8-12 weeks ]
  • (Mediator 6) Changes in systemic inflammation [ Time Frame: 8-12 weeks ]

Central Contacts and Locations

Central contacts

Hayyah Clairman

416-813-7979hayyah.clairman@sickkids.ca

Locations

University of Manitoba

Recruiting

Winnipeg, Manitoba, Canada, R3E 3P4

Principal Investigator:

Lily Lim, MBBS, MRCPCH, FRCPC, PhD

McMaster Children's Hospital

Recruiting

Hamilton, Ontario, Canada, L8N 3Z5

Principal Investigator:

Tania Cellucci, MD, MScCH, FRCPC

London Health Sciences Centre

Recruiting

London, Ontario, Canada, N6A 5W9

Principal Investigator:

Roberta Berard, MD, FRCPC, MSc

Centre Hospitalier Universitaire Sainte-Justine

Recruiting

Montreal, Quebec, Canada, H3T 1C5

Principal Investigator:

Jean Jacques De Bruycker, MD, FRCPC

More Information

Sponsor

The Hospital for Sick Children

Last update posted

Jul 29, 2026

Last verified

Jul, 2026

Keywords

  • arthritis
  • diet
  • microbiome

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by The Hospital for Sick Children on 2026-07-29.