500–2,000 mg/day of curcuminoids, with piperine or in a high-absorption formulation, with food.
Relieves knee pain in a way similar to an anti-inflammatory drug.
View the study (meta-analysis) →The isolated active compound lowers CRP and inflammation.
View the study (meta-analysis) →Possible support for the treatment of depression.
View the study (clinical trial) →⏱ 3 min read
Curcumin is the intense yellow polyphenol of turmeric (Curcuma longa), responsible for the characteristic color of curry and, according to an enormous scientific literature, also responsible for most of the therapeutic effects traditionally attributed to this spice; in the last two decades curcumin has become one of the most studied natural compounds in history, with thousands of publications on its anti-inflammatory, antioxidant, and multi-pathway-modulating properties relevant to chronic diseases.
The main problem with curcumin is its bioavailability: taken as raw turmeric or as an unformulated extract, curcumin is very poorly absorbed in the intestine and rapidly metabolized in the liver, resulting in very low plasma concentrations; modern formulations (with piperine, in a complex with phospholipids such as Meriva, with nanoparticles such as Theracurmin, or micellized) multiply absorption by 20 to 200 times and are the ones used in the clinical trials with the best results.
The indication with the best clinical evidence is knee osteoarthritis, where several meta-analyses of randomized trials have shown pain reductions comparable to ibuprofen or diclofenac with doses of 500 to 1,500 milligrams daily of formulated (bioavailable) curcumin, for 4 to 12 weeks; the effect is modest but clinically relevant, especially because it lacks the gastrointestinal and renal effects of pharmacological anti-inflammatory drugs.
In rheumatoid arthritis, the data are more limited but point in the same direction: curcumin as an adjunct to methotrexate or other DMARDs improves inflammation and morning stiffness without causing significant drug interactions in the available studies, which makes it a reasonable tool as nutritional support for standard treatment.
On systemic inflammatory markers such as C-reactive protein, meta-analyses show consistent and significant reductions in people with chronic low-grade inflammation, especially that associated with metabolic syndrome, type 2 diabetes, or chronic inflammatory diseases; the effect on specific markers such as interleukin-6, TNF-alpha, and MDA (malondialdehyde as a marker of oxidative stress) is well documented in multiple trials.
In diabetes and prediabetes, doses of 1,000 to 1,500 milligrams daily of formulated curcumin for 9 months significantly reduced the progression from prediabetes to diabetes in a Thai randomized trial with 240 participants, a robust finding that suggests an effect on long-term insulin sensitivity; in people with established diabetes, it modestly improves HbA1c and fasting blood glucose.
Several trials in major depression have shown antidepressant effects comparable to fluoxetine with doses of 1,000 milligrams daily for 6 to 8 weeks, especially when combined with standard treatment; the most plausible mechanism combines modulation of brain inflammation (known to be involved in refractory depression) with direct effects on neurogenesis and the availability of monoaminergic neurotransmitters.
In cognition and Alzheimer's prevention, epidemiological data from rural Asia, where turmeric consumption is high from childhood, suggest notably lower rates of Alzheimer's, and some brain imaging studies in older adults with chronic supplementation have shown promising changes in neuroinflammation biomarkers; formal clinical trials on dementia remain small and with heterogeneous results.
The most important thing is to use enhanced-bioavailability formulations: curcumin with piperine (as in Curcumin C3 Complex with BioPerine), phytosomal curcumin (Meriva, Theracurmin), or micellized curcumin (Novasol), because capsules of ground, unformulated turmeric have little documented clinical effect; effective doses range from 500 to 2,000 milligrams daily of formulated curcumin, divided into one or two doses with fatty meals.
It is generally well tolerated; the most frequent adverse effects are mild digestive discomfort at high doses; people taking anticoagulants (warfarin, acenocoumarol) should be cautious because of the theoretical antiplatelet effect that can increase bleeding, especially with piperine, which increases the bioavailability of many drugs at the same time; people with gallstones should consult first because curcumin increases gallbladder contraction and can precipitate colic.
Information, not medical advice. Scientific evidence reflects the quality of the studies.