An interventional study of Diet intervention in Arthritis, Juvenile, Arthritis, Childhood and Juvenile Idiopathic Arthritis, sponsored by The Hospital for Sick Children. Recruiting at 7 sites in Canada. Open to participants aged 8 Years to 18 Years. Per ClinicalTrials.gov, last updated 2026-07-29.
Sponsored by The Hospital for Sick Children · Not applicable, Interventional, and Supportive care
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.
365 studies on the registry are indexed under Arthritis, Juvenile; 101 are open to participants now.
This study's planned enrollment of 54 is close to the median of 52 across 230 interventional studies indexed under Arthritis, Juvenile.
Browse Arthritis, Juvenile studies →The Hospital for Sick Children is the lead sponsor of 578 studies on the registry; 83 are open to participants now.
Of its 7 completed or terminated interventional studies of FDA-regulated products, 1 (14%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Diet (MedDiet)
Other: 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.
(Feasibility 1) Participant accrual rate:
The proportion of all subjects who are approached that enroll and the accrual frequency at each site.
Time frame: 8-12 weeks
(Feasibility 2) The proportion of subjects who complete all the various measurement steps
Including return of the fecal samples, gender identification, completion rate of the food diary, etc. The proportion of subjects who continue in the 12-week extension will be recorded.
Time frame: 8-12 weeks
(Feasibility 3) Nutrient intake
Measured by the participants completing an ecologic momentary assessment (EMA) food diary and the corresponding Prospective Urban Rural Epidemiology (PURE) scores. The PURE score is calculated based on what the subjects entered in their EMA food diary. The score is from 0-6, with a higher score representing a healthier diet.
Time frame: 8-12 weeks
(Feasibility 4) Adherence to the MedDiet
Measured by Mediterranean Diet Quality Index in children and adolescents (KIDMED) a questionnaire that measures adherence to the MedDiet scores. The index ranges from 0-12. The values are classified into three levels: \> 8 is optimal MedDiet, 4-7 means improvement needed to adjust intake to MedDiet patterns, and ≤ 3 is low diet quality.
Time frame: 8-12 weeks
(Feasibility 5) Tolerability of diet intervention
Tolerability will be measured by the Gastrointestinal Symptom Scale for Kids (GISSK), a well-validated and simple questionnaire, designed for use in juvenile idiopathic arthritis (JIA). There are 2 parts to the scale. A visual analog scale (VAS) from 0-100 where the higher score represents the higher severity of gastrointestinal symptoms. And a 8-part questionnaire that ranges from 0-8 where 0 represents no gastrointestinal symptoms.
Time frame: 8-12 weeks
(Mediator 1) Changes in the microbiome
Measured by intestinal microbial ⍺-diversity (a measure representing the number of microbial groups and how evenly balanced they are within the gut), the individual species and functions of gut organisms (through shotgun metagenomics), and short chain fatty acids (SCFAs).
Time frame: 8-12 weeks
(Mediator 2) Changes in juvenile arthritis disease activity score
Measured by the Juvenile Arthritis Disease Activity Scale (cJADAS10). This includes the 1) physician's global assessment of disease activity measured on a 10cm visual analog scale (VAS), (2) parent/patient's global assessment of well-being measured on a 10cm VAS, (3) count of joints with active disease up to 10 active joints. The total score ranges from 0-30 with higher number representing a higher juvenile arthritis disease activity score.
Time frame: 8-12 weeks
(Mediator 3) Changes in functional status
Measured by the Childhood Health Assessment Questionnaire (CHAQ) (self/parent report scale that is widely used to measure functional status in children with arthritis). The score ranges from 0-3, with a 0 representing no functional disability and 3 representing severe disability.
Time frame: 8-12 weeks
(Mediator 4) Changes in quality of life
Measured by the Quality of My Life (QoML) questionnaire (a validated questionnaire to measure well-being). QoML consists of 3 visual analog scales each scored out of 10. Higher scores indicate better quality of life.
Time frame: 8-12 weeks
(Mediator 5) Changes in gut inflammation
Measured by fecal calprotectin.
Time frame: 8-12 weeks
(Mediator 6) Changes in systemic inflammation
Measured by a blood biomarker panel, a composite measure of immune activation comprising 49 analytes: (sCD40L, EGF, Eotaxin, FGF-2, Flt-3 ligand, Fractalkine, G-CSF, GM-CSF, GROα, IFNα2, IFNγ, IL-1α, IL-1β, IL-1ra, IL-2, IL-3, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-10, IL-12 (p40), IL-12 (p70), IL-13, IL-15, IL-17A, IL-17E/IL-25, IL-17F, IL-18, IL-22, IL-27, IP-10, MCP-1, MCP-3, M-CSF, MDC (CCL22), MIG, MIP-1α, MIP-1β, PDGF-AA, PDGF-AB/BB, RANTES, TGFα, TNFα, TNFβ, VEGF-A, YKL40)
Time frame: 8-12 weeks
(Confounder 1) Sleep quality
Measured by FitBit accelerometry
Time frame: 8-12 weeks
(Confounder 2) Patient-reported Sleep Quality
Measured by Patient-Reported Outcomes Measurement Information System (PROMIS) sleep disturbances questionnaire. The total score ranges from 0-40 with a higher score representing a poor sleep quality.
Time frame: 8-12 weeks
(Confounder 3) Physical activity
Measured by the Godin-Shephard Leisure-Time Physical Activity Questionnaire (GODIN) exercise questionnaire. A total score of 24 or more is active, 14 - 23 is moderately active, and less than 14 units is sedentary.
Time frame: 8-12 weeks
(Confounder 4) Sex
Results will be stratified by sex at birth.
Time frame: 8-12 weeks
(Confounder 5) Gender
Gender will be collected using the Perceived Similarity to Gender Groups Measure for children and youth.
Time frame: 8-12 weeks
(Confounder 6) Medication use
Will be abstracted from the patient chart. Results will be stratified by medication use.
Time frame: 8-12 weeks
(Confounder 7) Age
Stratify data by age group (8 - 12 and 13 - 18)
Time frame: 8-12 weeks
Not enrolling at this site.
Not enrolling at this site.
Not enrolling at this site.
Started Apr 2025 (actual). Primary completion is estimated for Aug 2028, 40 months after the start.
Of 53 non-industry interventional studies with no phase under Arthritis, Juvenile, half reached primary completion within 13 months of starting (the median), counting those still running; a quarter within 8 and three quarters within 35. This study's planned 40 months is above that.
Counting every sponsor, half of 56 studies reached it within 14 months; a quarter within 8 and three quarters within 39.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
The Hospital for Sick Children →