Academic rejects ‘fuzzy math’ claim in spat over curcumin bioavailability

Giovanni Appendino is professor of organic chemistry at the University of Eastern Piedmont, scientific advisor at natural ingredients supplier Indena, and co-author of the Cuomo et al study ​on curcumin just published in the Journal of Natural Products​.

He was speaking to NutraIngredients-USA.com after curcumin supplier EuroPharma issued a press release ​containing comments from Dr Ajay Goel, director of epigenetics and cancer prevention at the Gastrointestinal Research Center at Baylor University Medical Center in Dallas, challenging the study's figures.

In the release, Goel, who sits on EuroPharma’s scientific advisory board, said he had analyzed BCM-95 (a curcumin extract from EuroPharma), plain curcumin, and the Meriva curcumin phytosome used in the Cuomo study, and said the claimed increases in absorption in the study did not take into account the fact that less than a fifth of the phytosome was curcumin.

“The consequence of this mad race to discover the best curcumin preparation available in the marketplace has led to misleading marketing claims comparing curcumin absorption to turmeric in some instances, and fuzzy math and statistics in interpreting studies on curcumin with special absorption systems.”​

He added: “The two most important measures that support scientific logic remain. What levels of full-spectrum of curcuminoids can be detected in the blood? And how long do the curcuminoids remain in the blood stream within the therapeutic range?”​

Appendino: Our math is correct​

However, Appendino said: “We do not boast anything. We claim that curcuminoids are better absorbed from this​ [Meriva] formulation (by 29-fold) compared with unformulated curcumin. The fact that Meriva is only 20 percent curcumin is clearly stated​.

“On a weight basis, the improved absorption of curcuminoids from Meriva is six-fold, but, if you want to make a fair comparison with other products, you should also include in the comparison all the other formulation ingredients included in the formulation of the other products, like cellulose (also enclosed in the weight calculation of Meriva) or any other formulation adjuvants."​

Bioavailability and curcumin​

Meanwhile, EuroPharma ​chief of scientific affairs and education Cheryl Myers insisted that BCM-95 remained the most bioavailable product on the market.

She added: “If you emulsify curcumin with​ phosphatidylcholine​ [from soy lecithin] you have a phytosome​ with one part curcumin, two parts lecithin and two parts cellulose, so you get less than 100 mg of actual curcumin in a 500 mg supplement.​

“In comparing phytosome blood level results to those of BCM-95 curcumin, our product increased serum levels over twice as much as their curcumin phytosome on an equal weight basis.​

“Professor Appendino notes that on an equal weight basis (500 mg curcumin phytosome compared to 500 mg plain curcumin), that is only about a six-fold increase in absorption. Therefore, his 29-fold statistic is not comparing equal amounts of product.To make a 29-fold claim, the authors compared 500 mg curcumin phytosome to only 100 mg plain curcumin and computed the results in that manner." ​

BCM-95 was produced by a patented process that produced a product with up to 10 times the bioavailability of plain curcumin, she claimed. “We micronize curcumin powder and then blend it with essential oils from turmeric. ​In each 500 mg of BCM-95 curcumin, there is more than 450 mg full-spectrum curcuminoids.”​

Curcumin was poorly absorbed in the human body, she added.“Turmeric only has a tiny percentage of curcumin, which is very poorly absorbed, so you’d have to eat bucket loads of some of the products currently on the market to get any benefit​.”

The science behind curcumin​

BCM-95 was recently chosen by leading Alzheimer’s researcher Professor Ralph Martins ​for a new study exploring its ability to arrest the progression of dementia in Alzheimer’s patients at Edith Cowan University in Perth, added Myers.

Animal studies suggested curcumin could help reverse the build up of neural (beta amyloid) plaque implicated in Alzheimer's, she added. But more human intervention studies were needed. Professor Martin’s study was looking specifically at cognitive function and behavior, which would take the research onto a new level, she said.