Rebuttal of Negative Curcumin Research


An article was recently published in The Journal of Medicinal Chemistry titled “The Essential Medicinal Chemistry of Curcumin: Miniperspective.” In it, authors provide an overview of research on curcumin that they claim, “provides evidence that curcumin is an unstable, reactive, nonbioavailable compound and, therefore, a highly improbable lead.” This, like other negative research has been proliferated by the mainstream press, depicting this as proof that curcumin supplements provide no benefit. However, Ajay Goel, Ph.D., a professor and the director of Translational Genomics and Oncology, and the director of the Center for Gastrointestinal Research at the Baylor Scott & White Research Institute, Baylor University Medical Center in Dallas, TX, wrote a rebuttal, pointing out the limitations of the article as well as falsehoods.

The authors of the miniperspective contend that curcumin is not easily absorbed, is unstable and not water soluble. Goel does not disagree, however, many supplements marketed as “curcumin” are in fact formulated to include the whole family of curcuminoids which are curcumin, demethoxycurcumin and bisdemethoxycurcumin. These full spectrum formulations have been shown to offer enhanced absorption compared to curcumin isolated from other curcuminoids. While the researchers do state they will use the term “curcumin” interchangeably with “curcuminoids,” they also acknowledge that, “This Miniperspective will not attempt to address the potential therapeutic effects of even more complex turmeric extracts or preparations thereof but instead focuses on the reported utility of the chemical structure of the major constituent of these extracts: curcumin.” Therefore their conclusion cannot extend beyond this limited scope.

They also contend that in vitro results were not borne out in in vivo results and that no double-blinded, placebo-controlled clinical trial of curcumin has been successful. Goel challenges this, stating, “If they are referring to curcumin as a family of compounds, which most people do, it is not true. In the electronic database of the National Institutes of Health (NIH), available at, there are well over 9,000 published studies on curcumin, and if you just look at human, double blind, placebo controlled trials, there are more than 80 — the vast majority of which use enhanced absorption curcumin.”

Goel also takes issue with the objective of the article to explore the likelihood of curcumin as a drug candidate, which it conclude, is not. He explains that “curcumin cannot be reduced to a few chemical structures that behave in a singular fashion. There is a vast array of physical targets that are touched by the natural compounds in curcumin that cannot be duplicated by a synthetic drug. “