An alarming story of research fraud in the area of so-called alternative medicine (SCAM) is unfolding: Bharat B. Aggarwal, the Indian-American biochemist who worked at MD Anderson Cancer Center, focused his research on curcumin, a compound found in turmeric, and authored more than 125 Medline-listed articles about it. They reported that curcumin had therapeutic potential for a variety of diseases, including various cancers, Alzheimer’s disease and, more recently, COVID-19.
The last of these papers, entitled “Curcumin, inflammation, and neurological disorders: How are they linked?”, was publiched only a few months ago. Here is its abstract:
Background: Despite the extensive research in recent years, the current treatment modalities for neurological disorders are suboptimal. Curcumin, a polyphenol found in Curcuma genus, has been shown to mitigate the pathophysiology and clinical sequalae involved in neuroinflammation and neurodegenerative diseases.
Methods: We searched PubMed database for relevant publications on curcumin and its uses in treating neurological diseases. We also reviewed relevant clinical trials which appeared on searching PubMed database using ‘Curcumin and clinical trials’.
Results: This review details the pleiotropic immunomodulatory functions and neuroprotective properties of curcumin, its derivatives and formulations in various preclinical and clinical investigations. The effects of curcumin on neurodegenerative diseases such as Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), brain tumors, epilepsy, Huntington’s disorder (HD), ischemia, Parkinson’s disease (PD), multiple sclerosis (MS), and traumatic brain injury (TBI) with a major focus on associated signalling pathways have been thoroughly discussed.
Conclusion: This review demonstrates curcumin can suppress spinal neuroinflammation by modulating diverse astroglia mediated cascades, ensuring the treatment of neurological disorders.
The Anderson Cancer Center initially appeared to approve of Aggarwal’s work. However, in 2012, following concerns about image manipulation raised by pseudonymous sleuth Juuichi Jigen, MD Anderson Cancer Center launched a research fraud probe against Aggarwal which eventually led to 30 of Aggarwal’s articles being retracted. Moreover, PubPeer commenters have noted irregularities in many publications beyond the 30 that have already been retracted. Aggarwal thus retired from M.D. Anderson in 2015.
Curcumin doesn’t work well as a therapeutic agent for any disease – see, for instance, the summary from Nelson et al. 2017:
“[No] form of curcumin, or its closely related analogues, appears to possess the properties required for a good drug candidate (chemical stability, high water solubility, potent and selective target activity, high bioavailability, broad tissue distribution, stable metabolism, and low toxicity). The in vitro interference properties of curcumin do, however, offer many traps that can trick unprepared researchers into misinterpreting the results of their investigations.”
Despite curcumin’s apparent lack of therapeutic promise, the volume of research produced on curcumin grows each year. More than 2,000 studies involving the compound are now published annually. Many of these studies bear signs of fraud and involvement of paper mills. As of 2020, the United States National Institutes of Health (NIH) has spent more than 150 million USD funding projects related to curcumin.
This proliferation of research has fueled curcumin’s popularity as a dietary supplement. It is estimated that the global market for curcumin as a supplement is around 30 million USD in 2020.
The damage done by this epic fraud is huge and far-reaching. Hundreds of millions of taxpayer dollars, countless hours spent toiling by junior scientists, thousands of laboratory animals sacrificed, thousands of cancer patients enrolled in clinical trials for ineffective treatments, and countless people who have eschewed effective cancer treatment in favor of curcumin, were encouraged by research steeped in lies.