Coenzyme Q10 is not considered a vitamin or even an essential nutrient, since it can be produced in the human body from two amino acids, tyrosine and phenylalanine. That process requires the presence of pyridoxine, or vitamin B6. Some studies show that the liver, where Q10 is synthesized, becomes less efficient at producing Q10 with increasing age.
Indeed, other studies show that providing supplemental Q10 may help in treating diseases linked to aging, including Parkinson’s disease and congestive heart failure. Q10 helps protect against Parkinson’s because it provides potent antioxidant effects in the brain. One theory of what causes Parkinson’s disease is that an excess of iron increases in the brain, leading to oxidative reactions. In the substantia nigra area of the brain, where the neurotransmitter dopamine is produced, the excess oxidative reactions selectively destroy brain cells. Large doses of Q10 appear to blunt that out-of-control oxidation, helping to preserve the affected brain cells.
Q10 acts in the mitochondria of cells to aid electron transport, which means that it is involved in the synthesis of adenosine triphosphate, or ATP, the immediate energy source for all cells in the body. As large amounts of oxygen are used in the production of ATP, however, it also unavoidably produces larger amounts of free radicals, which are by-products of oxygen metabolism consisting of unpaired electrons. The unpaired electrons tend to combine with other electrons, and when that happens, havoc ensues.
Through its antioxidant activity, Q10 prevents the damaging effects of free radicals on susceptible parts of the cell, including the cell membrane and the inner portion of the mitochondria. That has enormous implications for protecting the health of various cells and tissues.
Q10 is thought to aid in the treatment of congestive heart failure because of its established role in the production of ATP. With congestive heart failure you have a relative failure of the cardiac cells to produce sufficient energy to fully support heart function. Giving supplemental Q10 to heart patients seems to bolster the flagging ATP synthesis found in failing hearts.
Another use for Q10 in cardiovascular disease relates to the widespread use of statin drugs to treat elevated blood lipids. The statins work by blunting an enzyme that produces cholesterol in the liver, but the liver cholesterol pathway is the same pathway that produces Q10, so in some people who use statin drugs, a deficiency of Q10 can occur. One of the hallmarks of that is myopathy, a destruction of muscle cells. Adding some supplemental Q10 to a statin drug regimen seems to cure the problem.
The widespread use of Q10 in every cell in the body led to its name, ubiquinone, because it’s ubiquitous—found everywhere. Q10 is particularly concentrated in low-density lipoprotein, which is the primary carrier of cholesterol in the blood. While elevated levels of LDL are thought to be a major risk factor for cardiovascular disease, the truth is that LDL is only dangerous when it becomes oxidized. The function of Q10 in LDL is to prevent such oxidation.
When LDL does become oxidized, however, Q10 is the first portion of LDL to get oxidized. In that sense Q10 can be viewed as the first line of defense against LDL oxidation. Not only that, but when other dietary antioxidants, including vitamins C and E, become oxidized, they convert into oxidants themselves. When sufficient Q10 is also present, though, the Q10 converts them back into antioxidants by donating an electron.
From an athletic perspective, the research on Q10 has been paradoxical, with some studies showing beneficial effects and others showing little or no benefits. One problem with Q10 supplements is that they are hard to absorb. In most cases you get only about 10 percent absorption—and the bigger the dose, the smaller the amount of absorption. Newer forms of supplemental Q10, such as ubiquinol, which is a reduced form of ubiquinone, offer about seven-times-greater absorption than standard Q10 supplements, although ubiquinol is also about twice as expensive. Some research suggests that the ubiquinol form is better for those over 40, since, as noted above, Q10 production in the body drops at about that age and ubiquinol is easier to absorb.
One meta-analysis, a compilation of previously published studies, related to the ergogenic, or athletic, use of Q10 found that while six studies showed some benefits, five other studies showed none. Another study of older adults involved a supplemental dose of 300 milligrams of Q10 a day for a month. Muscle biopsies showed that in the older folks who used supplemental Q10, certain changes occurred in gene expression in muscle, which resulted in a conversion of slow-twitch to fast-twitch muscle fibers. That’s significant because the fast-twitch fibers provide most of the muscle mass and strength. Fast-twitch fibers are lost with advancing age and lack of exercise, and slow-twitch fibers, which are weaker, dominate. So encouraging fast-twitch muscle fibers would help maintain muscle strength and mobility in older folks.
What about those who are under 40? Would supplemental Q10 also provide any athletic or muscle benefits? A new study examined that question.1 Unlike previous studies that have looked at the ergogenic effects of Q10, this one involved high-intensity exercise. Specifically, it involved a group of trained athletes running up the steepest mountain road in Europe. You don’t get much higher exercise intensity than that, since the race went on for 50 kilometers, or 31 miles and 126.6 yards, farther than a 26-mile marathon, and it was uphill! The runners took either Q10 or a placebo. The goal was to see if Q10 supplements could reduce muscle damage due to excessive oxidation and inflammation.
Rather than ingesting one or two larger doses of Q10, the athletes got a smaller dose, only 30 milligrams, two days before the test with dinner; three capsules with each of three meals the day prior to the race; one capsule on the day of the race; and one hour before undergoing a physical test. Using the smaller doses likely increased the rate of absorption. Although it wasn’t mentioned in the study, it’s also essential to take Q10 with a meal containing a large amount of fat to ensure absorption.
The results showed that those in the Q10 group had lower levels of creatinine, a marker of muscle damage after exercise. While the Q10 didn’t affect blood lipids significantly between the Q10 and placebo groups, the Q10 group did show slightly higher triglycerides. That would provide ergogenic effects during extensive exercise by providing both energy and also helping to conserve limited muscle glycogen.
Q10 also appeared to significantly blunt oxidative reactions, which prevented damage to cell membranes. That in turn would result in a lesser degree of muscle soreness after the exercise. It also tempered the activity of nitric oxide, which increases blood vessel diameter during exercise and thus the delivery of blood and oxygen to working muscles. In larger amounts, however, NO reverts to its free-radical form, causing damage to cells, particularly DNA. In this study Q10 protected against the DNA damage induced by higher levels of NO.
A high level of oxidative stress, as would occur with high-intensity exercise, also leads to a massive release of inflammatory cytokines. These are proteins related to immune function, many of which work by promoting inflammation. Excess inflammation in muscles is known to cause muscle breakdown. In fact, an increase in one of the inflammatory cytokines, tissue necrosis factor-a, is thought to be one of the major causes of muscle loss with age. TNF-a increases with body inflammation, and such inflammation is more common in older people.
This study shows that Q10 tempered the role of inflammatory cytokines, particularly TNF-a. It did this by blunting the release of nuclear factor kappa-B, which promotes the release of inflammatory cytokines in the body.
So, if you engage in intense exercise, supplemental Q10 may help lower the rate of muscle damage and inflammation. That’s particularly true if you are over 40, which is when the body becomes less efficient at synthesizing Q10. You can get smaller amounts of Q10 from natural food sources, such as meat, fish and eggs, but the average dose of Q10 derived from food alone is only 10 milligrams a day. For athletic purposes, a good range would be 100 to 300 milligrams a day in divided doses, always taken with a fat source.
1 Diaz-Castro, J., et al. (2012). Coenzyme Q10 supplementation ameliorates inflammatory signaling and oxidative stress associated with strenuous exercise. Eur J Nut. In press.