Formulating with curcumin: what does the research say?

Curcumin, the yellow compound in turmeric, reaches the blood poorly for three main reasons named in a widely cited 2007 review: poor absorption, rapid metabolism and rapid elimination. It is also practically insoluble in water. Researchers have tested several ways round this, including pairing it with piperine from black pepper, binding it to phospholipids, and making it into micelles, lipid particles or nanoparticles.

Why does so little curcumin reach the blood?

A widely cited review by Anand and colleagues (2007) names three main reasons curcumin has low bioavailability: it is poorly absorbed, it is metabolised quickly, and it is eliminated from the body quickly. On top of that, curcumin is practically insoluble in water at the pH of the stomach and gut (Dei Cas and Ghidoni, 2019); Tabanelli and colleagues (2021) put its solubility in pure water at about 0.6 µg/mL. For a formulator, that means plain curcumin clumps, floats or settles in water-based products, before absorption is even in question.

What approaches have researchers tested?

Reviews group the approaches into a few families:

Approach	What it is
Adjuvants	Curcumin taken with another ingredient, most often piperine from black pepper
Phospholipid complexes	Curcumin bound to phospholipids such as lecithin
Micelles	Curcumin carried inside tiny droplets formed by an emulsifier
Lipid particles and liposomes	Curcumin held in fat-based carriers
Nanoparticles	Curcumin made into, or carried in, particles measured in nanometres

Both Dei Cas and Ghidoni (2019) and Tabanelli and colleagues (2021) report that these approaches raised curcumin blood levels in animal and human studies. The size of the effect varies with the formulation, the dose and how the study was run, and a result for one product does not carry over to another, even one in the same family.

Is there a safety limit to design around?

Yes. JECFA, the joint FAO and WHO food additives committee, has set an acceptable daily intake for curcumin as a food colour, and EFSA confirmed the same figure in its 2010 re-evaluation. EFSA also noted that young children in some countries could exceed it where curcumin is used as a colour at the maximum permitted levels. When you plan a daily dose, count every source of curcumin in the product against that intake.

Where Athemin® fits

Athemin® is a nano-curcumin supplied as a liquid, so it disperses in water-based products such as drops and drinks. Its average particle size is 51.78 nm, measured on 30 particles by electron microscopy (HRTEM report HRTEM/2023/041-R). We only describe Athemin® from studies done on Athemin® itself, never from another company's product; every report behind our figures is listed on our Evidence page. Read What is nano-curcumin? for how particle size is measured.

Sources

1. Anand P, Kunnumakkara AB, Newman RA, Aggarwal BB. Bioavailability of curcumin: problems and promises. Mol Pharm 2007; 4(6): 807 to 818. PubMed 17999464
2. Dei Cas M, Ghidoni R. Dietary curcumin: correlation between bioavailability and health potential. Nutrients 2019; 11(9): 2147. PMC6770259
3. Tabanelli R, Brogi S, Calderone V. Improving curcumin bioavailability: current strategies and future perspectives. Pharmaceutics 2021; 13(10): 1715. PMC8540263
4. Joint FAO/WHO Expert Committee on Food Additives (JECFA), curcumin (INS 100i), acceptable daily intake, 61st meeting, 2003. who.int
5. EFSA Panel on Food Additives and Nutrient Sources added to Food. Scientific opinion on the re-evaluation of curcumin (E 100) as a food additive. EFSA Journal 2010; 8(9): 1679. efsa.europa.eu
6. Athemin^® particle size: HRTEM report HRTEM/2023/041-R, SERC HRTEM Laboratory, October 2023 (available to business partners on request).