The efficacy of high- and low-dose curcumin in knee osteoarthritis: A systematic review and meta-analysis

Hsiao AF, Lien YC, Tzeng IS, Liu CT, Chou SH, Horng YS · Complementary Therapies in Medicine

High-dose and low-dose curcuminoids relieved pain to the same degree and carried the same adverse-event rate, so no dose-response was detectable; curcuminoids beat NSAIDs on VAS pain.

Population

11 RCTs in primary knee osteoarthritis

Intervention

Curcuminoids at a daily dose of 1000 mg or more versus under 1000 mg

Comparator

Placebo or NSAIDs

Limitations

The dose cut-point ignores formulation, which is the variable that actually determines exposure, so a flat dose-response here is as consistent with dose not mattering as with dose being unmeasurable across products.