Efficacy of Turmeric Extracts and Curcumin for Alleviating the Symptoms of Joint Arthritis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Daily JW, Yang M, Park S · Journal of Medicinal Food

Pooled against placebo, turmeric or curcumin at about 1,000 mg/day lowered pain on a visual analogue scale by 2.04 points (95% CI 2.85 to 1.24 lower; p<0.00001) across 3 trials, and lowered pooled WOMAC and VAS pain scores by 15.26 points (95% CI 26.94 to 3.77 lower; p=0.009). Against active comparators — ibuprofen, diclofenac and glucosamine, pooled together as 'pain medicine' across 5 trials — the difference was 1.89 points (95% CI 4.13 lower to 0.35 higher; p=0.10), which is a null result rather than a demonstration of equivalence. The authors judge their own evidence base insufficient for definitive conclusions.

Population

8 randomized trials of turmeric/curcumin in arthritis, seven in knee osteoarthritis and one in rheumatoid arthritis

Intervention

Turmeric extracts or curcumin, typically ~1000 mg/day for 8-12 weeks

Comparator

Placebo, or an active comparator the review pools as "pain medicine" — ibuprofen, diclofenac, glucosamine and chondroitin

Limitations

Eight trials totalling 937 subjects met the review's criteria; two of them reported no means or standard deviations, so the meta-analyses rest on six trials pooled three, three and five at a time. Seven studied knee osteoarthritis and one rheumatoid arthritis. Formulations, doses and comparators are heterogeneous, and the active-comparator pool mixes NSAIDs with glucosamine and chondroitin. The paper's abstract and results section disagree on the WOMAC pooling, reporting it as four studies at -15.36 and as three studies at -15.26.