Today almost all Q10 documentation has been done using the oxidized form of Q10, called ubiquinone. This is the only form of Q10 that has documented good absorption and 25 years of safety data and a long list of human studies.
Ubiquinone -- Ubiqinone -- Ubidecarenone -- Myoquinone -- Myoqinon -- Bio-Qinone -- Normal Q10 -- Oxidized Q10-- The original Q10 -- Q -- QX -- CoQ -- CoQ10 -- 2,3-dimethoxy-5-methyl-6-decaprenyl-1,4-benzoquinon (clear yellowish color)
Mioquinon -- Mioqinone -- Myoqinone
Ubiquinol -- Ubiqinol -- Uniqinol -- BioActive Q10 -- Reduced Q10 -- QH -- QH2 -- CoQH -- Dihydroquinone -- 2,3-dimethoxy-5-methyl-6-poly prenyl-1,4-benzoquinol (introduced 2006, milky-white color)
Normal Q10 is called ubiquinone. This is the only kind that has been available as a supplement since the first Q10 preparations were introduced in Europe shortly after 1990. Globally, ubiquinone has also been the only form of Q10 whose effect has been documented in scientific studies right up until the introduction of the reduced form of Q10 (ubiquinol) in 2006. Since 2006, there has not been much, if any, noteworthy scientific evidence on ubiquinol. In other words: Almost all documentation on the prevention and treatment of Q10 deficiency has been performed with ubiquinone, and this research includes studies involving the use of Bio-Quinone. Ubiquinol, on the other hand, is still just a theoretical supposition with no studies that can be compared with, for example, the rigor and the power of the Q-symbio study.
At the molecular level, the difference between ubiquinone (normal / oxidized Q10) and ubiquinol (reduced Q10) is not great, but the difference is significant. Ubiquinol has two extra hydrogen molecules, and, in conjunction with oxygen, it forms a so-called hydroxyl group on the "head" of the Q10 molecule, which is itself a quinone ring.
As shown by the following, there is absolutely no reason to think of oxidized Q10 as something inferior, inactive, or less effective. Both forms of Q10 are needed in the body, and the Q10 molecules are constantly changing from one form to the other. However, the two forms of Q10 have quite different roles in the body.
To simplify matters: The oxidized ubiquinone is needed to produce energy in the form of ATP, and the reduced ubiquinol functions as an antioxidant. What this means is that the reduced Q10 delivers electrons whereas the oxidized Q10 receives electrons, which is why we say that one form is no better than the other. Furthermore, the Q10 from our diet comes in the form of oxidized Q10. The Q10 that we produce in the liver is also oxidized Q10, whereas 90-95% of Q10 in the blood is in the form of reduced Q10. Q10 is absorbed in the intestine along with fat. It is then slowly transported with the lymphatic vessels to the blood. Already during passage through the intestinal wall, oxidized Q10 changes to reduced Q10. Logically, there is no good reason to choose a product containing reduced (ubiquinol) as the body will automatically convert oxidized (ubiquinone) to reduced (ubiquinol). In the cells' mitochondria, the two forms constantly switch from one form to the other many times per second - that is, from the oxidized form to the reduced form and back again. A Q10 product's ability to be absorbed from the intestine is one of its most important aspects. Ubiquinone of good quality has been found to be absorbed as well as ubiquinol. Thus, in the normal course of events, there is abolutely no reason to spend extra money on buying ubiquinol instead of ubiquinone.