Efficacy and safety of different curcumin formulations in osteoarthritis: an umbrella review of systematic reviews

Background This umbrella review synthesizes evidence from systematic reviews and meta-analyses evaluating the efficacy and safety of diverse curcumin formulations in the treatment of osteoarthritis (OA). The objective is to assess curcumin’s therapeutic potential and inform future formulation development. Methods A systematic search was conducted across PubMed, Web of Science, Cochrane, Embase, Scopus, and MEDLINE up to September 2025 to identify systematic reviews and meta-analyses investigating curcumin for OA (requiring at least one randomized controlled trial). Methodological quality was assessed using AMSTAR-2. Due to limited data and substantial heterogeneity in formulations and study designs, findings were synthesized qualitatively. Results Ten meta-analyses and systematic reviews were included. Curcumin formulations exhibited significant improvements in pain (VAS) and joint function/stiffness (WOMAC), showing efficacy signals comparable to non-steroidal anti-inflammatory drugs (NSAIDs) and a more favorable tolerability profile in the available studies. However, methodological and clinical heterogeneity was substantial (AMSTAR-2 rated only three studies as high quality). Variations in curcumin composition, bioavailability-enhancing strategies, and extraction methods, coupled with the absence of direct comparative analyses among formulations, precluded definitive inter-group comparisons. Conclusion Curcumin-based interventions show promise for OA symptom management, with efficacy signals comparable to NSAIDs and appear to have a more favorable tolerability profile in the available studies, while addressing bioavailability challenges. Nevertheless, pronounced heterogeneity and the lack of head-to-head comparative studies, and incomplete safety reporting across reviews preclude definitive conclusions regarding superiority over NSAIDs or optimal formulations, and formulation-specific inferences remain limited. Future research should prioritize high-quality comparative trials or network meta-analyses to confirm efficacy signals and enable formulation-specific inferences. Systematic review registration https://www.crd.york.ac.uk/PROSPERO , identifier CRD420251172722.