NOW again tests CoQ10 and quercetin products bought on and finds no improvement in quality


Recently, the company turned its attention back to CoQ10 and quercetin, retesting some supplements previously tested and testing some new ones, and found that there was “no improvement in policing quality.”

Photo ©

Photo ©

Starting in 2017, supplements industry giant NOW began purchasing dietary supplements from various, often lesser known, brands sold on and testing them for content and potency. Finding many products not meeting their label claims, NOW alerted and FDA about these deficiencies. At this point, NOW has tested products in many product categories, including CoQ10 and quercetin. Recently, the company turned its attention back to CoQ10 and quercetin, retesting some supplements previously tested and testing some new ones, and found that there was “no improvement in policing quality.”

The company reexamined eight CoQ10 products it tested and found to be of low potency back in 2020. According to the company’s latest press release, after retesting those products in April 2022, NOW “found the same serious problems remain for seven out of eight brands tested,” with seven out of eight brands containing less than 30% of the potency claimed. Not only that, but many products were mislabeled by “misrepresenting potencies through deceptive labeling tricks.”

For instance, says NOW, “Clear Formulas, aSquared, Foxy Doc, and Healthy Way brands all mislabel their product as ‘400 mg / 6%’ potency. This is deceptive when the front panel says ‘400 mg’ potency and the Amazon title says ‘CoQ10 400 mg Max Strength.’ The customer gets less than 24 mg CoQ10 per capsule,” because the product only contains a percentage of the full potency. But by reading the label, the consumer might assume that the full 400-mg potency is in the product.

NOW purchased and tested three samples per product using HPLC. Testing was performed not only internally at NOW’s labs but also by third-party lab Eurofins.

NOW adds that “It is apparent by looking at lot numbers and bottle types that the same manufacturer is supplying multiple brands with the same fraudulent products…”

NOW also recently tested a large group of quercetin supplements purchased on According to the company, quercetin demand grew during the COVID-19 pandemic, causing raw material costs to increase. Higher ingredient prices lead to higher risk of low-potency products, even though labels might claim the product is high potency.

The company found that 20 out of 24 quercetin product brands tested were below 90% label potency, with 14 out of 24 actually containing less than 50% of the labeled potency. It also found the same labeling deception happening with the quercetin products, with some companies labeling their products as containing “18% potency” but inferring the consumer gets more quercetin than that.

Another problem detected involved quercetin dihydrate. As NOW’s press release explains, “Quercetin dihydrate 95% is the raw ingredient used in supplements, and some brands claim ‘400 mg quercetin’ while others may claim ‘420 mg quercetin dihydrate’ and the potency is identical. Some brands label as ‘quercetin dihydrate’ to show a higher label claim, although this is not normal. Quality brands such as NOW input at least 10% overage quercetin dihydrate in order to compensate for quercetin dihydrate being 95% quercetin.”

Another problem NOW detected in its testing of both ingredients is companies claiming that their capsules are vegan or vegetarian when they actually contain gelatin.

NOW said it again plans to send its findings to Amazon, FDA, and the FTC, hoping that some progress can be made in addressing these problems. Despite NOW’s previous attempts to warn the retailer and regulators, it appears, upon retesting, that many problematic products are still being sold on Amazon.

“NOW has reported these findings to Amazon directly, as we did previously, but the products continue to be sold and often as a ‘sponsored’ (paid marketing) featured products,” said Dan Richard, vice president of global sales and marketing for NOW.

Recent Videos
woman working on laptop computer by window
Related Content
© 2024 MJH Life Sciences

All rights reserved.