Written by Alexa Heathorn, MS, CNS-c, Science Writer. Daily supplementation with 10 g of inulin for 8 weeks reduced CRP, improved tender and swollen joint counts, lowered disease activity scores, enhanced hand-grip strength, reduced morning stiffness, and improved quality of life in adults with rheumatoid arthritis.

Rheumatoid arthritis (RA) is a multifactorial autoimmune disease characterized by chronic joint inflammation, functional impairment, fatigue, and increased risk for systemic complications such as cardiovascular disease, pulmonary dysfunction, and elevated inflammatory biomarkers¹. Globally, RA affects approximately 0.46% of the population, translating to nearly 18 million individuals in 2019, underscoring its substantial clinical and societal burden. Despite advances in treatment, there is still no cure for RA, and current therapies focus primarily on symptom control and slowing disease progression^1,2. First-line medications—including corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs)—can offer meaningful symptom relief but are associated with significant long-term risks such as gastrointestinal ulceration, hepatic and renal damage, headaches, dizziness, weight gain, decreased bone density, and increased susceptibility to infection¹. As a result, the need for adjunctive, low-risk therapeutic strategies is growing, particularly those that may modulate inflammation and support quality of life.

Emerging research has highlighted the gut–immune connection in RA, with multiple studies showing that individuals with RA exhibit marked alterations in gut microbiota composition compared to healthy controls¹. These shifts often include reduced levels of Bifidobacterium species and lactic acid–producing bacteria, taxa strongly associated with intestinal and immune health. Diet plays a central role in shaping the gut microbiome, and dietary patterns rich in prebiotics and probiotics have demonstrated potential to improve microbial balance, reduce inflammation, and influence disease severity in RA¹.

Prebiotic of growing interest are inulin-type fructans (ITFs), indigestible, fermentable fibers naturally found in foods such as chicory root, garlic, onions, leeks, wheat, bananas, soybeans, artichokes, and asparagus¹. ITFs are recognized for their ability to stimulate the growth of beneficial bacteria such as Bifidobacterium and Lactobacillus, enhance production of short-chain fatty acids, support intestinal barrier integrity, and modulate immune activity. Although animal studies have suggested that inulin may improve inflammatory markers and delay arthritis progression, no clinical trials had evaluated inulin supplementation alone in humans with RA. To address this gap in research, a recent randomized, triple-blind, parallel clinical trial was conducted to evaluate the impact of inulin supplementation on inflammatory indices, clinical outcomes, and quality of life in adults with rheumatoid arthritis¹.

The study included 60 adults with rheumatoid arthritis, all over the age of 18, who were randomly assigned to receive either 10 g of inulin or a maltodextrin placebo per day for 8 weeks¹.  Outcomes assessed included erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), morning stiffness, pain intensity, hand-grip strength, disease activity (DAS-28), and quality of life using the health assessment questionnaire (HAQ).

The results were as follows after 8 weeks of supplementation:

• Inflammation:
  • The inulin group showed a significant reduction in CRP (p = 0.02), with levels decreasing only in the inulin group. ESR also declined within the inulin group (p = 0.005), although between-group differences were not significant after full adjustment.
• Joint symptoms:
  • Tender and swollen joint counts improved in both groups, but reductions were significantly greater with inulin (tender joints p = 0.002; swollen joints p = 0.04). Pain intensity decreased similarly in both groups, with no significant difference between them (p = 0.11).
• Disease activity:
  • Both groups saw improvements in DAS-28, but the inulin group experienced a more pronounced reduction in overall disease activity (p = 0.02).
• Functional capacity:
  • Hand-grip strength increased substantially in the inulin group (p < 0.001), with improvements exceeding those of placebo (p = 0.02).
• Morning stiffness:
  • Morning stiffness improved only in the inulin group (p < 0.001), and between-group differences favored inulin (p = 0.02).
• Quality of life:
  • HAQ scores improved significantly with inulin (p < 0.001), while no improvement occurred in the placebo group. Overall differences favored inulin (p = 0.02).

Potential limitations of the study:

• The sample size was modest (60 participants), which may limit the statistical strength and generalizability of the findings to broader RA populations.
• The study population consisted of adults with active rheumatoid arthritis and without major comorbidities; therefore, results may not apply to individuals with milder disease, severe disability, pediatric RA, or those with significant coexisting medical conditions.
• The intervention period was relatively short (8 weeks), so the long-term effects, durability of improvements, and extended safety profile of inulin supplementation remain unknown.
• Dietary intake of inulin-rich foods and gut microbiome composition were not assessed, making it unclear whether shifts in microbiota or diet-related factors influenced the outcomes.
• A specific high-performance inulin supplement (10 g/day) was used, so results may not be generalizable to other types, doses, or forms of inulin or prebiotic fibers.

Daily supplementation with 10 g of inulin for 8 weeks improved several clinical outcomes in adults with rheumatoid arthritis, including reductions in inflammatory markers, tender and swollen joint counts, morning stiffness, disease activity scores, and improvements in hand-grip strength and quality of life. These findings suggest that inulin may serve as a safe, well-tolerated, and accessible adjunct to standard RA therapy, particularly for individuals seeking non-pharmacologic strategies to support symptom management and inflammation. While results are promising, further research with larger sample sizes, longer intervention periods, and broader inflammatory and microbiome analyses is needed to confirm these benefits, understand underlying mechanisms, and determine whether similar improvements extend to different populations, doses, or forms of prebiotic fibers.

Source: Tabatabaeyan A, Grigorian A, Salesi M, Fiezi A, Kafeshani M. Inulin supplementation improves some inflammatory indices, clinical outcomes, and quality of life in rheumatoid arthritis patients. Sci Rep. Aug 21 2025;15(1):30732. doi:10.1038/s41598-025-16611-3.

© The Author(s) 2025

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Posted November 25, 2025.

Alexa Heathorn, MS, CNS-c, is a clinical nutritionist specializing in metabolic health, hormonal balance, and gastrointestinal restoration through root-cause functional nutrition. She earned her master’s degree in Nutrition from Bastyr University and is currently a Certified Nutrition Specialist (CNS) candidate. Alexa also works as a research writer and functional health consultant, translating complex science into actionable strategies for practitioners and wellness companies. Learn more at www.bloomedwellness.com.

References:

1. Tabatabaeyan A, Grigorian A, Salesi M, Fiezi A, Kafeshani M. Inulin supplementation improves some inflammatory indices, clinical outcomes, and quality of life in rheumatoid arthritis patients. Sci Rep. Aug 21 2025;15(1):30732. doi:10.1038/s41598-025-16611-3
2. Organization WH. Rheumatoid Arthritis. Updated 2023, June 28. 2025. https://www.who.int/news-room/fact-sheets/detail/rheumatoid-arthritis