Curcumin
curcumin · turmeric extract · curcuminoids
The active turmeric polyphenol promoted as a natural anti-inflammatory.
TypeSupplement / dietary
Grade
C
Limited
- Class
- Anti-inflammatory
- Primary use
- Inflammation & joint support
- Evidence strength
- medium
- Last reviewed
- 2026-07-01
Bottom line
A credible anti-inflammatory with decent trials for osteoarthritis pain — held back by famously poor absorption. Useful for specific symptoms, not a proven longevity molecule.
What the evidence says
Curcumin has one of the larger supplement trial bases, with reasonable evidence that it reduces knee-osteoarthritis pain (in some trials comparable to NSAIDs, with fewer GI effects) and lowers some inflammatory markers. The persistent problem is bioavailability: plain curcumin is barely absorbed and rapidly metabolised, so results depend heavily on the formulation (piperine-enhanced, phospholipid, nanoparticle). There are no longevity outcome trials. Grade C: real symptomatic and anti-inflammatory effects, no aging endpoints, and formulation-dependent.
Key studies
- [1]
Curcumin for knee osteoarthritis pain (RCTs / meta-analysis) · meta-analysis
Reduced pain, sometimes comparable to NSAIDs in small trials.
PubMed ↗ - [2]
Curcumin bioavailability and formulations · review
Absorption is the limiting factor; formulation matters more than dose.
PubMed ↗ - [3]
Curcumin and inflammatory markers (review) · review
Modest reductions in some inflammatory markers.
PubMed ↗
Mechanism
Modulates inflammatory signalling (e.g. NF-κB, COX-2) and acts as an antioxidant. Native bioavailability is very low, so enhanced formulations or co-administration with piperine are used to raise exposure.
Safety
Generally well tolerated. High doses can cause GI upset; curcumin can inhibit platelet aggregation and interact with anticoagulants, and rare cases of liver enzyme elevation have been reported with certain enhanced products. Choose reputable, contaminant-tested brands.
Dosage context
Trials range widely (~500–2000 mg/day of curcuminoids), almost always with a bioavailability enhancer. Comparing products is hard because 'curcumin' on a label can mean very different absorbed doses.
From the field
Curcumin is the rare herbal with genuine osteoarthritis data — and the poster child for 'the dose on the label isn't the dose in your blood'. We grade it C and pay attention to formulation, not marketing.