Curcumin

The active compound in turmeric (Curcuma longa)

Real anti-inflammatory signal in joint trials, undermined by curcumin's own biggest practical problem: it barely absorbs unless the formula does something about it.

What the evidence supports

Moderate Knee osteoarthritis pain Several trials against placebo and one head-to-head against an NSAID show comparable pain reduction over 4–12 weeks.

Moderate Inflammatory markers Meta-analyses show reductions in CRP, but effect size varies enormously by formulation and dose.

Limited Mood & depression A handful of small trials report benefit; sample sizes and follow-up are too thin to call it settled.

Dose used in trials

500–1,000 mg

per day, and only when paired with piperine or a bioavailability-enhanced form — plain curcumin powder is very poorly absorbed.

Safety

Generally tolerated

GI upset at high doses. Can lower blood sugar and thin blood modestly.

Ask a doctor first if

Three cases

On blood thinners, diabetes medication, or scheduled for surgery.

The absorption problem

Why "curcumin" on a label often means very little

Unenhanced curcumin has extremely low oral bioavailability — most of it is metabolised before it reaches circulation. The positive trials almost all used a piperine-paired, phospholipid, or nanoparticle formulation. A label that just says "curcumin extract" with no bioavailability technology named is a red flag, regardless of the milligram number.

Knee OA trial vs. diclofenac, 139 patients

Four weeks, curcuminoid extract vs. an NSAID. Pain and function scores improved comparably in both arms, with fewer GI side effects in the curcumin group. Open-label, not blinded — a real limitation given pain is subjective.

Curcumin

What the evidence supports

The absorption problem

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