Coenzyme Q10 capsules

The thing is, there are considerable differences in the absorption and bioavailability of the many commercial CoQ10 supplements.  An inexpensive CoQ10 supplement is not inexpensive if it gives only negligible absorption and bioavailability.  It is a waste of money.  It is important to choose a CoQ10 supplement with documented absorption and efficacy.

The active substance in the best Coenzyme Q10 nutritional supplements is a natural substance that is extracted in a yeast fermentation process; the Coenzyme Q10 is not a synthetic substance.

The CoQ10 molecules in the best nutritional supplements are the same molecules as the CoQ10 molecules synthesized inside the mitochondria in human cells.

As we get older, our cells’ ability to synthesize Coenzyme Q10 declines. Furthermore, the use of some drugs such as statin medications inhibits the cells’ synthesis of Coenzyme Q10.  We need a good supplement to make up for the loss.

Absorption and Bio-availability of Coenzyme Q10

Similar to vitamin E, Coenzyme Q10 in food and in nutritional supplements has a low absorption and bio-availability. In the case of Coenzyme Q10, the difficult absorption is attributed to the relatively large size and the lipid soluble nature of the CoQ10 molecules.

The crystalline CoQ10 raw material has a melting point above 118 degrees Fahrenheit, far higher than the temperatures in the stomach and the small intestines. The manufacturer of a good CoQ10 nutritional supplement must process the CoQ10 raw material in such a way as to ensure that the CoQ10 crystals will dissolve to single molecules at body temperature. The human intestinal absorption cells cannot absorb CoQ10 crystals; it can absorb only single CoQ10 molecules [Judy 2007].

Dr. William Judy

In his 2018 Insider’s Guide to Coenzyme Q10, Dr. William V. Judy, SIBR Research, devotes 23 pages to a discussion of the absorption and bioavailability of Coenzyme Q10. The book is available from ISBN: 978-87-7776-186-7.

CoQ10 molecules are too large to be absorbed directly into the blood. Instead, the CoQ10 molecules that manage to enter the intestinal absorption cells are packed in chylomicrons and released into the lymphatic system. The CoQ10 cells move slowly through the lymph until they reach the thoracic duct near the heart and enter the blood circulation [Judy 2007].

Form and Formulation of CoQ10 Supplements

The Coenzyme Q10 used in nutritional supplements has two forms: the oxidized form called ubiquinone and the reduced form called ubiquinol.

The ubiquinone form has several advantages:

Efficacy of CoQ10 Supplements

The best clinical trials of the efficacy of CoQ10 supplements have been done using a pharmaceutical-grade ubiquinone Coenzyme Q10, not a food-grade Coenzyme Q10, in preparations produced in the same way as medicines are produced:

Safety of CoQ10 Supplements

Properly manufactured Coenzyme Q10 supplements are non-toxic with no observed serious undesirable side effects and no serious interactions with other medications [Hathcock 2006].

The safety of Coenzyme Q10 in healthy adult volunteers has been evaluated in a randomized, double-blind, placebo-controlled study at doses of 300, 600 or 900 mg/day for four weeks. The frequency of adverse events, e.g. common cold symptoms and gastrointestinal effects, was not significantly different between the placebo control and CoQ10 group. Generally, Coenzyme Q10 was well tolerated at up to 900 milligrams per day, a dosage far higher than the dosage (100 to 300 milligrams daily) needed for therapeutic purposes [Hidaka 2008].

Read our key article on CoQ10 as adjuvant therapy for heart failure


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Judy, W. V., Stogsdill, W. W., Judy, D. S., & Judy, J. S. (2007). Coenzyme Q10: Facts or Fabrications? Natural Products Insider. Retrieved from

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Mohr, D., Bowry, V. W., & Stocker, R. (1992). Dietary supplementation with Coenzyme Q10 results in increased levels of ubiquinol-10 within circulating lipoproteins and increased resistance of human low-density lipoprotein to the initiation of lipid peroxidation. Biochimica et Biophysica Acta, 1126(3), 247-254.

Mortensen, S. A., Rosenfeldt, F., Kumar, A., Dolliner, P., Filipiak, K. J., Pella, D., & Littarru, G. P. (2014). The effect of coenzyme Q10 on morbidity and mortality in chronic heart failure: results from Q-SYMBIO: a randomized double-blind trial. JACC. Heart Failure, 2(6), 641-649.

Mortensen, A. L., Rosenfeldt, F., & Filipiak, K. J. (2019). Effect of Coenzyme Q10 in Europeans with chronic heart failure: A sub-group analysis of the Q-Symbio randomized double-blind study. Cardiology Journal, 26(2): 147-156.

Singh, R. B.,Niaz, M. A., Sindberg, C. D.,Moesgaard, S.,& Littarru, G. P. (2005). Effect of oral coenzyme Q10 dosages on serum Q10 and MDA levels among healthy men. Paper presented at the International Coenzyme Q10AssociationMeeting Abstracts, Los Angeles.

Zhang, Y., Liu, J., Chen, X. & Chen, C-Y. (2018). Ubiquinol is superior to ubiquinone to enhance Coenzyme Q10 status in older men. Food & Function, 9: 5653-5659.

The information presented in this review article is not intended as medical advice and should not be used as such.

Please click here for additional information about the absorption and bio-availability of Coenzyme Q10 supplements.

25 July 2020