What is curcumin?
Curcumin is the yellow pigment and main active compound of the turmeric root (Curcuma longa). It is a polyphenol and the best-studied constituent of the spice. Turmeric powder contains only about 2 to 5 % of it, and the body absorbs it very poorly.
Curcumin explained simply
Curcumin is a yellow-orange plant compound from the rhizome of the turmeric plant. It gives curry its colour and has been part of Ayurvedic cooking and tradition for centuries. Scientists have been interested in it for decades because in laboratory and animal experiments it has been linked to many metabolic processes, such as inflammatory messengers and oxidative stress.
Strictly speaking "curcumin" is a single compound, but extracts usually contain three related compounds together, the curcuminoids: curcumin itself (the largest share), demethoxycurcumin and bisdemethoxycurcumin. Labels often say "curcuminoids" or "curcumin" without separating the two cleanly, so it pays to check the exact wording.
Turmeric powder and curcumin extract compared
Typical orders of magnitude as described in our articles.
| Feature | Turmeric powder | Curcumin extract |
|---|---|---|
| Feature Curcumin content | Turmeric powder about 2 to 5 % | Curcumin extract often standardised to up to about 95 % |
| Feature Other constituents | Turmeric powder essential oils, starch, fibre | Curcumin extract hardly any, highly purified |
| Feature Uptake without aids | Turmeric powder low, often under 1 % of the compound in the blood | Curcumin extract also low unless specially formulated |
| Feature Typical use | Turmeric powder cooking, flavour | Curcumin extract supplements, studies |
Why is curcumin so hard to absorb?
Curcumin is lipophilic and practically insoluble in water. In the watery environment of the gut it clumps together. The small part that crosses the gut wall is quickly modified chemically (glucuronidation) in the gut wall and liver and excreted, so free curcumin is present in the blood only briefly. Its bioavailability is therefore naturally low.
There are several approaches to this: taking it with a fatty meal, adding piperine from black pepper (which can also affect the breakdown of medication), micelles, phytosomes or inclusion complexes with cyclodextrin.
What do studies tell us?
There are very many laboratory studies on curcumin and a growing number of clinical trials, for example on joint complaints, digestion or inflammatory markers. The results are mixed: some studies show improvements in questionnaires or lab values compared with placebo, others do not. Common limitations are small groups, short durations and inconsistent preparations. Because products differ so much, the results of one study cannot simply be transferred to every turmeric product.
Curcumin is not a medicine, and no food supplement can cure or prevent a disease. Quality and purity also matter: reputable manufacturers have each batch tested in the lab (for example by HPLC) and provide a certificate of analysis.
Curcumin may affect blood clotting and the breakdown of some medicines. If you take medication, especially anticoagulants, talk to your doctor first. Caution is also advised with gallstones or bile duct disease.
Curcumin is usually well tolerated at common amounts. Possible side effects are stomach upset or diarrhoea. During pregnancy, with bile duct disease and when taking anticoagulants, seek medical advice first. This is not medical advice.
Curcumin in Curcumin+
Curcumin+ contains curcumin as an inclusion complex with γ-cyclodextrin (1000 mg complex with 200 mg curcuminoids per daily serving of 2 capsules), without piperine, in a pullulan capsule. In a small pilot study of a γ-cyclodextrin formulation (European Journal of Nutrition, 12 healthy adults), about 39 times the total curcuminoids and 85 times the curcumin (AUC, dose-normalised) were measured compared with an unformulated standard extract. The study tested another manufacturer's commercial product made by a different process. Curcumin+ is made by the kneading method; there is no absorption study of Curcumin+ itself, so these figures cannot be transferred directly. That describes absorption, not an effect on any disease.
Frequently asked questions about curcumin
Is curcumin the same as turmeric? No. Turmeric is the plant or spice; curcumin is one of its constituents, namely the yellow main active compound.
How much curcumin is in turmeric? About 2 to 5 % in the powder. Extracts are standardised to much higher contents.
Can you absorb enough curcumin from food? From the spice in meals only small amounts, with low uptake. That is no cause for concern: turmeric in cooking is a food, not a study preparation.
How long until you notice something? Studies usually measure after several weeks. It is not an acute remedy, and whether you notice anything is individual.
