NOW testing raises concerns about potency, heavy metals, label accuracy, & synthetics in curcumin supplements

By Stephen Daniells

- Last updated on GMT

© frank600 / Getty Images
© frank600 / Getty Images

Related tags Curcumin Turmeric Dietary supplements Quality control

Supplement manufacturer NOW alleges that among 23 “unknown” curcumin products it purchased recently on Amazon and subjected to in-house and third-party analytical testing, 12 products failed at least one of the tests.

NOW, which is based in Bloomingdale, IL, released the testing results today. The company purchased 23 unknown brand product samples plus two NOW products in June 2021 and tested them to assess how much of the respective active ingredients they contained.

Preliminary testing revealed that only one product clearly failed potency testing and four others tested very low, but without any specific label claim.  However, additional testing revealed that 12 out of the 23 failed either for potency, containing synthetic curcuminoids, heavy metals, or used gelatin caps instead of the claimed veggie caps, said NOW.

On the plus side, 11 out of 23 did pass all tests, though with slightly misleading labeling (confusing use of “turmeric”, “turmeric extract”, “turmeric curcumin”, “curcumin extract”, and so on), said NOW.

For heavy metals (arsenic, cadmium, lead, and mercury), the average total heavy metals, by product, were 525% higher than NOW’s two sample average, and only one product out of 23 had less heavy metals than NOW. Two brands allegedly had lead levels above California’s Prop 65 limits.

All of these products were tested for potency both at the company’s highly respected internal labs and at Eurofins Labs.  The assay method was RP-HPLC with UV detection and potencies were determined based on total curcuminoids per capsule.

Tests for synthetic curcumin were performed at the University of Georgia’s Center for Applied Isotope Studies, which revealed that four out of 23 unfamiliar brands were spiked with “fossil fuel derived organic carbon”. 

Dan Richard, VP of Global Sales & Marketing, NOW, told NutraIngredients-USA that the data has been shared with Amazon. “We have not yet shared with FDA, but will share openly with all parties including FDA,”​ he added.

NutraIngredients-USA contacted Amazon for comment but did not receive a response prior to publication.

Hot category

The turmeric/ curcumin supplement category has enjoyed meteoric growth over the last decade. According to the 2019 Herb Market Report​ published by the American Botanical Council (HerbalGram​ 127), turmeric is the number two selling herb in the natural channel, with $48.1 million in sales. It is number four in the mass channel (MULO) with $92.4 million in sales.

Consumer awareness and understanding of the botanical’s potential benefits are now very high, with data from the ITC Insights 2020 Consumer Survey showing that 86% of supplement consumers are familiar with curcumin/turmeric.

The Global Curcumin Association (GCA) has also been focusing on curcumin quality and has tested products purchased online for the presence of synthetical curcuminoids for several year, with over 50% of the batches tested in 2018 and again in 2020 failing, according to a review article by Traci Kantowski, GCA's Communications Director, on NutraIngredients-USA​. Sabinsa, the founding member of GCA, helped to pioneer the carbon isotope method to test for synthetic curcumin​.

The issue of adulteration with synthetic curcumin has been highlighted several times over the years. The Botanical Adulterants Prevention Program (BAPP), spearheaded by the American Botanical Council in cooperation with the American Herbal Pharmacopoeia and the National Center for Natural Products Research, has published both a bulletin​ and a lab guidance​ about the issue. 

NOW’s Richard explained that there are very few labs able to perform the radiocarbon testing necessary to determine the presence of synthetic curcuminoids. “It is also an extra test beyond normal quality control since most brands would simply test Curcumin/Turmeric for potency and not the source,” ​he said. “Because this is a known problem in the industry, quality brands should also test to confirm their products are not spiked with synthetics.”

Dietary supplement quality specifications

Amazon is gearing up to launch its dietary supplement quality program, first announced in December 2020. A substantial update was issued in April​. Dietary supplement brands initially had until May 3, 2021 to submit the necessary documents, with Amazon aiming to give approval prior to May 31, 2021, but this date has been pushed back several times, and appears to be delayed again.

“While we appreciate Amazon’s initial efforts to address these ongoing, egregious problems with sellers on their platform, there is clearly still a long way to go,”​ said Richard.

NOW puts online supplements under the microscope

Over the years NOW has built up an extensive analytical laboratory at its main manufacturing site and headquarters in Bloomingdale.  In 2020, NOW decided to use that expertise to test the quality of supplements sold on Amazon, test results which were verified by third party labs.

To date, NOW has tested sets of CoQ10, SAMe​, phosphatidylserine​ and alpha lipoic acid (ALA)​ products and compared them to NOW’s own offerings in those categories. Few products in any category came close to meeting label claim for potency of the stated active ingredients, and a number of the bottles contained almost none of the active ingredient.

Richard confirmed that NOW will continue testing different categories in the future to find out if Amazon’s proposed quality standards are having an effect. 

“Some products are more susceptible to cheating or quality errors, and it appears that Curcumin is in better shape than products such as Phosphatidyl Serine, CoQ10 and SAMe,”​ he said. “Still, nearly half of products tested failed in at least one important quality test.  We do hope that Amazon’s new quality steps will clean up brands that don’t have good quality control.  This has been delayed, so that enforcement is not in place today.”

NOW’s ongoing efforts to publicize quality concerns about supplements purchased on Amazon were recognized by NutraIngredients-USA with the 2021 NutraIngredients-USA Award for Industry Initiative of the Year​.

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