Third-Party Testing Finds Widespread Ubiquinol Label Discrepancies

Editor’s note: this is a follow-up to Erin McEvoy’s previous July coverage.

A third phase of independent testing on finished ubiquinol supplements has again found that products did not contain meaningful amounts of the ingredient listed on their labels, according to results announced by Kaneka Nutrients, a raw material supplier for the ingredient.^1,2

None of four newly tested, Amazon-sourced products contained more than a trace of ubiquinol, extending a pattern first identified in testing rounds conducted in mid-2025 and again in late 2025. For manufacturers competing in the coenzyme Q10 supplement category, the finding adds to a growing body of evidence that ingredient authenticity, not just formulation or clinical support, has become a live sourcing risk.

"These findings confirm what we've built our reputation on for decades: sourcing matters," said Ken Tsuchibe, CEO of Soft Gel Technologies, a contract manufacturer that uses Kaneka's ubiquinol in one of its branded ingredients. "When manufacturers and consumers choose CoQH-CF, they know exactly what they're getting—genuine Kaneka Ubiquinol in a crystal-free formulation backed by published clinical research."

How Was the Ubiquinol Testing Conducted, and What Did It Find?

Kaneka's testing program, run through the independent laboratory Eurofins, has evaluated 3 successive batches of finished ubiquinol products purchased from Amazon, with products shipped directly from the retailer to the laboratory to preserve chain of custody and limit the possibility of mishandling before analysis.²

In the first phase, 11 products tested below their labeled dosage, several measuring under 0.005 mg per serving against label claims typically in the hundreds of milligrams; 2 results were reported as inconclusive. A second phase covering nine additional products in December 2025 produced similar results, with all measuring below 0.005 mg per serving. In the most recent round, 4 products measured between less than 0.001 and less than 0.003 mg per serving.²

Why Does the Distinction Between Ubiquinol and Ubiquinone Matter?

Coenzyme Q10 occurs in the body in 2 interconvertible forms: ubiquinone, the oxidized form, and ubiquinol, the reduced form. One published crossover study found plasma coenzyme Q10 levels were roughly 70% higher in participants who took ubiquinol compared with ubiquinone at an equivalent dose.³

The body can convert between the 2 forms as needed, but that conversion capacity appears to decline with age and in certain health conditions, which is part of the rationale manufacturers cite for formulating with ubiquinol specifically in products aimed at older adults.

Formulation also affects how much of an ingested dose reaches circulation: one randomized crossover trial found a solubilized, crystal-free ubiquinol formulation produced several times greater blood coenzyme Q10 levels than a conventional crystalline formulation after a single dose.⁴ Both findings depend on a basic premise, that the finished product contains the labeled ingredient in a bioavailable form, which is precisely what this testing program has repeatedly called into question.

What Are the Limitations of This Testing Effort?

The sample is limited to products purchased through a single retail channel, Amazon, and does not represent the broader market of ubiquinol products sold through other retailers or directly by brands. The testing methodology, sample sizes, and statistical handling have not been published in a peer-reviewed format, and the identities of the flagged products and brands have not been disclosed, limiting independent verification.

References

1. Third-party testing reveals many ubiquinol supplements do not meet label claims. Soft Gel Technologies. August 28, 2026. Accessed September 1, 2026. https://www.nutritionaloutlook.com/view/kaneka-nutrients-ubiquinol-authenticity-testing-results

2. McEvoy E. Kaneka Nutrients releases third phase of ubiquinol authenticity testing results. Nutritional Outlook. July 23, 2026. Accessed September 1, 2026. https://www.nutritionaloutlook.com/view/kaneka-nutrients-ubiquinol-authenticity-testing-results

3. Langsjoen PH, Langsjoen AM. Comparison study of plasma coenzyme Q10 levels in healthy subjects supplemented with ubiquinol versus ubiquinone. Clin Pharmacol Drug Dev. 2014;3(1):13-17. doi:10.1002/cpdd.73

4. Evans M, Baisley J, Barss S, Guthrie N. A randomized, double-blind trial on the bioavailability of two CoQ10 formulations. J Funct Foods. 2009;1(1):65-73. doi:10.1016/j.jff.2008.09.010