Comparative efficacy of nutraceutical interventions for arthritis management: A network meta-analysis of randomized controlled trials

Dietary supplements are increasingly used in arthritis management, but their comparative effectiveness remains uncertain. This network meta-analysis (NMA) compared the effects of curcumin, omega-3 fatty acids, probiotics, and vitamin D in adults with arthritis. PubMed, Scopus, Web of Science, and Cochrane Library were searched up to October 2025 for randomized controlled trials. A frequentist NMA with P-scores was performed, and certainty of evidence was assessed using CINeMA. Forty-four RCTs involving 3,163 participants were included. Omega-3 supplementation reduced C-reactive protein (CRP) (MD: −2.86; 95% CI: −4.12 to − 1.60; low certainty) and increased HDL-C (MD: 0.04; 95% CI: 0.02 to 0.07; moderate certainty). Probiotics reduced triglycerides (MD: −27.97; 95% CI: −30.35 to − 25.58) and total cholesterol (MD: −27.23; 95% CI: −33.36 to − 21.10), with moderate certainty. Probiotics also improved WOMAC pain in the primary analysis, but this effect was not sustained in sensitivity analyses. Curcumin reduced rheumatoid factor levels (MD: −135.20; 95% CI: −160.28 to − 110.11; low certainty) and improved VAS pain. Omega-3 improved DAS28 in the primary analysis, but this effect was not robust after sensitivity analysis. Significant heterogeneity was observed across most outcomes (I² >80%). Dietary supplements may provide selective adjunctive effects in arthritis, including omega-3 for CRP reduction, HDL-C increase, and disease activity improvement, probiotics for TG and TC reduction, and curcumin for pain and immunological markers. However, substantial heterogeneity, limited evidence certainty, and inconsistent sensitivity analyses warrant cautious interpretation.