Inulin for Osteoarthritis

(OA-INULIN Trial)

Overseen By Evelyn Hsieh, MD, PhD

Age: 18+

Sex: Any

Trial Phase: Phase 2

Sponsor: Yale University

Must not be taking: Antibiotics, Proton pump inhibitors

Disqualifiers: Diabetes, Gastrointestinal disease, others

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 8

Duration: 8 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to determine if inulin, a type of dietary fiber, can reduce inflammation in individuals with knee osteoarthritis. Participants will take either inulin or a placebo daily for 8 weeks to assess its effect on knee pain and inflammation markers in the blood. The study seeks individuals who have experienced knee pain most days in the past month and have been diagnosed with knee osteoarthritis. As a Phase 2 trial, this research measures inulin's effectiveness in an initial, smaller group, providing participants an opportunity to contribute to important findings.

Will I have to stop taking my current medications?

The trial requires that you do not use certain medications that affect the gut microbiome, like proton pump inhibitors or specific arthritis drugs. If you're on these, you may need to stop them to participate.

Is there any evidence suggesting that inulin is likely to be safe for humans?

Research has shown that inulin supplements are usually safe for adults. One study found that taking 8 to 18 grams daily is safe for up to 24 weeks. The most common side effects are mild, such as bloating or gas. Some people notice these stomach issues, but they are typically not serious. Overall, inulin appears safe for short-term use in most people. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising?

Researchers are excited about inulin for osteoarthritis because it offers a novel approach compared to standard treatments, which often include pain relievers and anti-inflammatory drugs. Inulin is a type of dietary fiber that may help manage inflammation through a different mechanism by promoting gut health and improving metabolic factors. Unlike typical medications that focus directly on symptom relief, inulin works by potentially enhancing the body's natural ability to reduce inflammation and pain. This method could offer a more holistic and sustainable way to manage osteoarthritis symptoms.

What evidence suggests that inulin might be an effective treatment for osteoarthritis?

Research has shown that inulin, a type of dietary fiber, might help reduce inflammation in people with knee osteoarthritis. Participants in this trial will receive either 10 grams or 15 grams of inulin daily, or a placebo. In an 8-week study, individuals who took 10 grams of inulin each day experienced improvements in their symptoms and joint function. Inulin appears to lower inflammation, leading to less pain and better movement. Other studies have also found that inulin can enhance the quality of life for those with joint problems. These findings suggest that inulin could be helpful in managing knee osteoarthritis symptoms. ^{1 2 4 6 7}

Who Is on the Research Team?

Evelyn Hsieh, MD, PhD

Principal Investigator

Yale University

Are You a Good Fit for This Trial?

This trial is for older adults with knee osteoarthritis who experience inflammation and pain. Participants will be randomly assigned to receive either a dietary fiber supplement or a placebo for two months.

Inclusion Criteria

Stated willingness to comply with all study procedures and availability for the duration of the study (8 weeks)

Established patient in the VA Connecticut Healthcare System

Agreement to adhere to lifestyle considerations throughout study duration, including maintenance of current diet, physical activity, and avoidance of new dietary supplements or complementary therapies

Exclusion Criteria

Participation in another interventional study or use of an investigational drug within the past 30 days

Use of anti-inflammatory dietary supplements within the past 30 days

Known allergy or intolerance to components of the study intervention, including inulin or maltodextrin

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive either inulin or placebo for 8 weeks to assess changes in inflammation and knee pain

8 weeks

Baseline and 8 weeks

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Inulin

Trial Overview The study is testing if inulin, a prebiotic fiber, can lower blood markers of inflammation and reduce knee pain compared to a placebo (maltodextrin) over an 8-week period.

How Is the Trial Designed?

Group I: Inulin 15 g/day Experimental Treatment 1 Intervention

Participants receive inulin powder in identical sachets. Dose is escalated to 15 g daily (5 g daily for 3 days, 10 g daily for 4 days, then 15 g daily). Sachets are mixed with food or beverage and taken once daily with the largest meal, for 8 weeks.

Group II: Inulin 10 g/day Experimental Treatment 1 Intervention

Participants receive inulin powder in identical sachets. Dose is escalated to 10 g daily (5 g daily for 3 days, then 10 g daily for 4 days). After Week 2, participants continue with one 15 g sachet containing a 2:1 blend of inulin and maltodextrin, providing a daily dose of 10 g inulin. Sachets are mixed with food or beverage and taken once daily with the largest meal, for 8 weeks.

Group III: Placebo (Maltodextrin) Placebo Group 1 Intervention

Participants receive maltodextrin powder in identical sachets. Dose is escalated over 2 weeks to match the dosing schedule of the inulin arms (5 g daily for 3 days, 10 g daily for 4 days, then 15 g daily). Sachets are mixed with food or beverage and taken once daily with the largest meal, for 8 weeks.

Who Is Running the Clinical Trial?

Yale University

Lead Sponsor

Trials

1,963

Recruited

3,046,000+

VA Connecticut Healthcare System

Collaborator

Trials

86

Recruited

8,800+

National Center for Complementary and Integrative Health (NCCIH)

Collaborator

Trials

886

Recruited

677,000+

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8025512/

Effect of a prebiotic supplement on knee joint function, gut ... The aim of this study is to examine if prebiotic oligofructose-enriched inulin reduces knee joint pain and improves knee function, thereby ...

2. clinicaltrials.gov clinicaltrials.gov/study/NCT07189585

Inulin Supplementation for Reducing Inflammation and ... This study will test whether inulin, a type of dietary fiber, can reduce inflammation in older adults with knee osteoarthritis.

3. nature.com nature.com/articles/s41598-025-16611-3

Inulin supplementation improves some inflammatory ... Our findings suggest that an 8-week regimen of 10 g of inulin supplementation can significantly improve disease activity, HAQ, hand grip ...

4. trialsjournal.biomedcentral.com trialsjournal.biomedcentral.com/articles/10.1186/s13063-021-05212-w

Effect of a prebiotic supplement on knee joint function, gut ... The secondary outcomes include change in knee pain, change in body composition (fat mass and lean mass), and change in quality of life in adults ...

5. sciencedirect.com sciencedirect.com/science/article/abs/pii/S0955286324001323

Dietary pectin and inulin: A promising adjuvant supplement ... Inulin supplementation improves some inflammatory indices, clinical outcomes, and quality of life in rheumatoid arthritis patients. 2025, Scientific Reports ...

6. webmd.com webmd.com/vitamins/ai/ingredientmono-1048/inulin

Inulin - Uses, Side Effects, and More It is possibly safe in adults when taken as a supplement, short-term. Doses of 8-18 grams daily have been used safely for up to 24 weeks. The most common side ...

7. fishersci.com fishersci.com/store/msds?partNumber=AAA1842509&productDescription=INULIN+10G&vendorId=VN00024248&countryCode=US&language=en

SAFETY DATA SHEET No protective equipment is needed under normal use conditions. Recommended Filter type: Particle filter. Hygiene Measures. Handle in accordance ...