This 2021 systematic review evaluated the efficacy and safety of all types of Curcuma longa extract versus placebo for knee osteoarthritis (OA) treatment. A total of 10 RCTs with 783 patients were eligible. Authors found that Curcuma longa extract was associated with significantly better pain relief and functional improvement compared with placebo for knee OA. Moreover, the smallest effect sizes of VAS for pain and WOMAC total score exceeded the minimum clinically important differences (MCIDs).
Dai W, Yan W, Leng X, Chen J, Hu X, Ao Y. Effectiveness of Curcuma longa extract versus placebo for the treatment of knee osteoarthritis: A systematic review and meta-analysis of randomized controlled trials. Phytother Res. 2021 Nov;35(11):5921-5935. doi: 10.1002/ptr.7204. Epub 2021 Jul 2. PMID: 34216044.