Bill Judy Picture

Dr. William Judy, founder and director of the SIBR Institute, is arguably the world’s leading expert on Coenzyme Q10 absorption. He has led numerous lab studies and animal studies and clinical trials on the absorption and effects of Coenzyme Q10 preparations.

We know that Coenzyme Q10 is an essential co-factor in at least three important processes in the body: cellular energy production, cellular and lipid antioxidant defense, and regulation of endothelial cell function. We know that our adult bodies produce less Coenzyme Q10 with increasing age, and we know that most of us cannot make up the difference through the food that we eat [6]. From the age of 40 on, we need a good Coenzyme Q10 supplement daily.  I asked Dr. William Judy what is involved in getting a good Coenzyme Q10 supplement.

Beneficial health effects of Coenzyme Q10 supplements
Coenzyme Q10 molecules are distinguished in two ways:

  • They are fat-soluble, lipophilic molecules
  • They are redox molecules, capable of giving up (oxidation) and taking on (reduction) electrons in chemical reactions

Well-absorbed Coenzyme Q10 supplements have beneficial health effects on heart failure patients [7], on patients taking statin medications [2] on healthy elderly individuals [1], and on veterans suffering from Gulf War Illness [3]  I asked Dr. William Judy, the founder of the SIBR Institute, what it takes to make a well-absorbed Coenzyme Q10 preparation [5].

Coenzyme Q10 supplements cannot be in crystalline form
First of all, said Dr. Judy, it is important to know that the body cannot absorb a crystalline form of any substance and that the Coenzyme Q10 crystals will not dissociate into single molecules at body temperature [4]. The Coenzyme Q10 raw material comes in the form of crystals, and we humans just cannot absorb them.  We would need a body temperature of 50 degrees Celsius to be able to dissociate the CoQ10 crystals to single molecules in the stomach and small intestine.  Remember: normal body temperature is 37 degrees Celsius.

Q10 crystals

The dry powder Coenzyme Q10 raw material needs careful processing if it is going to be absorbed in the small intestine.

Coenzyme Q10 in the ubiquinone form dissolved in vegetable oils
To be absorbed, the Coenzyme Q10 supplement must be of a crystal-free formulation.  How can we tell if a preparation is crystal-free?  Well, for a start, we can rule out any tablets or capsules containing CoQ10 powder.  What we are looking for is a Coenzyme Q10 supplement that has the Coenzyme Q10 in its ubiquinone form pre-heated and dissolved in vegetable oil inside soft gelatin capsules.

The three forms of Coenzyme Q10 in the body
Dr. Judy explained that there are three forms of Coenzyme Q10 in the body:

  • The ubiquinone form, which is the oxidized form, the form that is an electron acceptor, is the stable form of Coenzyme Q10.  It is the form that has been used in the clinical trials that have produced statistically significant health benefits. It is the form that plays a vital role in the bio-energetics of the cells. It has a bright yellow-orange color inside the capsule.
  • The semi-ubiquinone form, which is a partially oxidized and partially reduced form, is a less stable form of Coenzyme Q10.  It is not commercially available.
  • The ubiquinol form, which is the completely reduced form, the form that is an electron donor, is the very unstable form of Coenzyme Q10.  It is the form that serves as an antioxidant quenching harmful free radicals.  It has a milky white color inside the capsule.  It has been available commercially since 2007 but has not been tested in randomized controlled trials to the extent that ubiquinone preparations have been.

Why Coenzyme Q10 in the ubiquinone form?
Why does Dr. Judy insist on taking a Coenzyme Q10 supplement in the ubiquinone form?  Dr. Judy’s studies have shown that there are three good reasons:

  1. The ubiquinol substance is very unstable and difficult to work with. There is always the chance that the ubiquinol in the capsule will be oxidized to ubiquinone in the capsule, so why not buy the ubiquinone form?
  2. The ubiquinol that is in the capsule will be converted in the stomach and in the small intestine to ubiquinone in any case before the Coenzyme Q10 molecules reach the absorption cells in the small intestine.
  3. The ubiquinol preparations have not been tested and proven in rigorous trials in the way that the best ubiquinone preparations have been.

What happens when you swallow a Coenzyme Q10 capsule?
Here, step by step, is what Dr. Judy says will happen when you swallow a Coenzyme Q10 supplement:

  • The Coenzyme Q10 moving through your stomach and your small intestine will be almost 100% in the form of ubiquinone regardless of which form you ingest.
  • The Coenzyme Q10 in the ubiquinone form will be absorbed across the absorption cell membranes in the small intestine into the lymph vessels.
  • In the distal portion of the abdominal lymph duct (distal meaning closer to the intestinal absorption cells and farther away from the lymph trunk vessel), the concentration of Coenzyme Q10 in the form of ubiquinone will be approximately seven times greater than the concentration of Coenzyme Q10 in the ubiquinol form, according to measurements done by Dr. Judy. These measurements are definitive evidence that Coenzyme Q10 is absorbed in the ubiquinone form. In the transport from the intestinal absorption cells to the lymph and in the lymph itself, the conversion of the Coenzyme Q10 molecules from ubiquinone molecules to ubiquinol molecules takes place.
  • When, then, the Coenzyme Q10 reaches the proximal portion of the abdominal lymph duct (proximal meaning farther away from the intestinal absorption cells and closer to the lymph trunk vessel), nearly 98% of the Coenzyme Q10 has been converted from the ubiquinone to the ubiquinol form, again, according to measurements done by Dr. Judy and colleagues in animal studies.
  • Consequently, in the thoracic lymph duct, the body’s largest lymph vessel, the concentration of Coenzyme Q10 is predominantly in the reduced form, the ubiquinol form.
  • Accordingly, the Coenzyme Q10 molecules that reach the blood circulation, where their concentration peaks approximately 6 – 8 hours after ingestion, are about 96% in the form of ubiquinol.  Dr. Judy explains that the blood plasma is full of harmful free radicals and is, therefore, in need of a lipophilic antioxidant like Coenzyme Q10 in its ubiquinol form.

Why the long roundabout route to the blood circulation?
Dr. Judy explains that the Coenzyme Q10 molecules are too big to be able to diffuse from the intestinal absorption cells directly into the intestinal capillaries and, from there, into the blood.  If it were possible for the Coenzyme Q10 molecules to go directly from the intestinal absorption cells into the blood, he says, then we should see the concentration of the ingested and absorbed Coenzyme Q10 peak in the blood within 1.5 to 2 hours after ingestion. But we do not.  The absorbed Coenzyme Q10 move rather slowly through the lymph system before entering the blood circulation.

Higher concentration of Coenzyme Q10 in the lymph than in the blood
Dr. Judy made an interesting observation.  Because there is not nearly as much fluid in the lymph compartment as there is in the blood compartment – only approximately 1/10 as much fluid in the lymph compartment – the concentration of absorbed Coenzyme Q10 is much higher in the lymph than it is in the blood.

So, a well-absorbed 100-milligram Coenzyme Q10 supplement might result in the following discrepancies in the Coenzyme Q10 concentration levels:

  • In the distal portion of the abdominal lymph duct: 8.7 micrograms per milliliter of ubiquinol and 1.3 micrograms per milliliter of ubiquinone.
  • In the blood plasma 6 hours later: 0.74 micrograms per milliliter of ubiquinol and 0.04 micrograms per milliliter of ubiquinone.

Remember: Bio-synthesis of Coenzyme Q10 declines with age in our adult years
We need to take a well-absorbed Coenzyme Q10 supplement.  Fortunately, there are some safe and affordable Coenzyme Q10 supplements with a proven track record in randomized controlled trials.


  1. Alehagen, U., Johansson, P., Björnstedt, M., Rosén, A., & Dahlström, U. (2013). Cardiovascular mortality and N-terminal-proBNP reduced after combined selenium and coenzyme Q10 supplementation: a 5-year prospective randomized double-blind placebo-controlled trial among elderly Swedish citizens. International Journal of Cardiology, 167(5), 1860-1866.
  2. Folkers K, Langsjoen P, Willis R, Richardson P, Xia LJ, Ye CQ, et al. Lovastatin decreases coenzyme Q levels in humans. Proc Natl Acad Sci U S A 1990;87:8931-4.
  3. Golomb, B. A., Allison, M., Koperski, S., Koslik, H. J., Devaraj, S., & Ritchie, J. B. (2014). Coenzyme Q10 benefits symptoms in Gulf War veterans: results of a randomized double-blind study. Neural Computation, 26(11), 2594-2651.
  4. Judy, W. V., Stogsdill, W. W., Judy, D. S., & Judy, J. S. (2007). Coenzyme Q10: Facts or Fabrications? Natural Products Insider.  Retrieved from
  5. Judy, W. V. (2016). Private communication.
  6. Kalen A, Appelkvist EL, Dallner G. Age-related changes in the lipid compositions of rat and human tissues. Lipids. 1989;24(7):579–584.
  7. 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.