Briefly about CoQ10 Supplementation
Did you know that people who eat a healthy, varied diet typically consume less than 10 mg of CoQ10 each day? Even if you routinely eat foods that are rich sources of this vital nutrient, such as meat, poultry, oily fish, and organ meats, you may not be getting enough for optimal health.
CoQ10 is a crucial nutrient. It is involved in 90% of the body’s energy production and it contributes to the metabolism that gives you healthy muscles, bones, and skin. CoQ10 is unique because it protects your cells from oxidative stress (without suffering damage itself), which becomes even more important as we age. CoQ10 also helps your body maintain proper pH, which may improve overall immune function and prevent the development of some diseases.
CoQ10 supplementation can be especially helpful for certain individuals, including those taking statin medications and people suffering from heart ailments, high blood pressure, high cholesterol, diabetes, fibromyalgia, or neurological disorders such as Parkinson’s disease or Huntington’s disease. However, people with certain health conditions and those who are taking certain medications should consult their doctor before supplementing with CoQ10.
Recommended dosages
| Healthy adults | 30 to 100 mg daily |
| Therapeutic doses | 100 to 300 mg daily, divided throughout the day |
| Under medical supervision | Up to 3,000 mg daily |
CoQ10 supplements are most effective when taken in softgel form, and are best absorbed when taken alongside a meal containing fat.
Why CoQ10 is Crucial for Health
CoQ10 plays a vital role in the body’s ability to convert nutrients into energy. Because 90% of the body’s total energy production requires this particular coenzyme, a lack of CoQ10 would significantly hinder cellular metabolism, resulting in fatigue and muscle pain. The complex biochemical transformation of nutrients into energy takes place in microbodies called mitochondria, which are found inside nearly all of the body’s cells, with the exception of red blood cells. Inside the mitochondria, CoQ10 is involved in a chain of reactions that results in the production of the energy-rich molecule adenosine triphosphate (ATP). Each individual cell must produce its own energy to carry out its functions. Cells that require more energy have more mitochondria and require more CoQ10 to supply them with more ATP. During ATP production, when CoQ10 accepts electrons, it is considered reduced and it becomes known as ubiquinol. When reduced CoQ10 donates electrons, it is considered oxidized and it becomes known as ubiquinone. The ability of CoQ10 to switch back and forth between these two forms allows it to maintain the electron balance that is essential for the synthesis of energy.[1, 2]
As the only antioxidant that the human body can manufacture, CoQ10 plays a major role in protecting our bodies from oxidative damage.[2, 3, 4] This is important because electrons are constantly being exchanged during normal molecular processes. When certain molecules lose electrons, they become unstable free radicals that can cause oxidative stress by stealing electrons from the body’s cells. Antioxidants prevent cell damage by providing the required electrons or by breaking down the free radicals.[5, 6, 7] CoQ10 is unique among antioxidants in that it can contribute and receive electrons without being damaged itself. As humans age, our need for antioxidants increases, due to a range of factors such as declining CoQ10 production, a general increase in inflammation, and the body’s reduced ability to perform normal processes efficiently.[1]
Another property of CoQ10’s antioxidant ability is that it can increase blood flow and protect blood vessels by reducing the damage caused by oxidized low-density lipoprotein (LDL) particles. For example, having enough CoQ10 is thought to minimize the hardening of the arteries, formally known as atherosclerosis.[8, 9, 10, 11] CoQ10 can be especially beneficial for individuals with heart ailments, especially those with a history of heart attacks, coronary heart disease, high blood pressure, and high cholesterol. CoQ10’s antioxidant properties and its vital roles in maintaining energy production and blood flow are particularly helpful to the cardiovascular system.[12] CoQ10 may also reduce the symptoms associated with congestive heart failure, such as leg swelling, difficulty breathing due to fluid in the lungs, and decreased exercise capacity.
According to one clinical study, starting daily CoQ10 supplementation within three days of a heart attack could make subsequent heart attacks and chest pain less likely. It might also reduce the risk of death due to heart disease. Furthermore, taking CoQ10 supplements before heart surgery is likely to improve a patient’s recovery by limiting oxidative cell damage, boosting heart function, and making arrhythmia less likely.[13]
An analysis of 12 clinical studies focusing on the effect of CoQ10 on blood pressure determined that CoQ10 may be able to lower systolic blood pressure by as much as 17 mm Hg and diastolic blood pressure by 10 mm Hg, but it may take several months to achieve results.[13] CoQ10 has the potential to lower blood sugar and might help lower high blood pressure in people with diabetes, although diabetics should always talk to their doctor before beginning CoQ10 supplementation.[13, 60]
Although CoQ10 does not appear to directly lengthen life span, its fundamental role in energy production contributes to a healthy metabolism and the upkeep of muscles, bones, skin, and other tissues. CoQ10 levels in body tissues decrease with age, and this is thought to be linked with declining energy levels and organ function.[15, 16, 20]
The removal of cellular waste and debris is a very important bodily function that is performed by lysosomes. These organelles require a permanent supply of protons in order to maintain an environment with the optimal pH. CoQ10 is a primary carrier of these protons and is integral to maintaining proper pH, which may improve overall immune function and prevent the development of certain diseases.[12, 18, 19]
Increased oxidative stress is thought to have a link with neurological disorders such as Parkinson’s disease and Huntington’s disease. People with these nervous system disorders often have low blood levels of CoQ10, which performs a vital role in transporting the electrons necessary for proper nerve and brain function.[20] In one study involving 80 patients in the early stages of Parkinson’s disease who did not require treatment for their illness, those taking CoQ10 supplements did not become as disabled as those in the placebo group during the 16-month trial. The study also found that better outcomes were linked to progressively higher CoQ10 doses.[21]
In several studies, taking daily CoQ10 supplements helped relieve symptoms related to fibromyalgia, including headache, pain, fatigue, and tender points, and brought cellular CoQ10 levels closer to those of control patients.[24, 25, 26, 23]
CoQ10 may also play a role in improving male fertility. Although it is not thought to increase sperm count or improve sperm morphology (shape), CoQ10 may improve sperm motility. Motility (spontaneous and active movement) requires energy, which in turn requires a strong assist from the mitochondria and CoQ10.[27, 28]
Oral supplementation with CoQ10 may alleviate the symptoms of fatigue in healthy individuals engaging in physical exercise, and may increase exercise tolerance for those suffering from heart conditions.[29, 30, 31]
Internal Processing of CoQ10
The biosynthesis of CoQ10 has not been exhaustively studied, but it is known that after ingestion, the absorption of CoQ10 is similar to the absorption of fat-soluble antioxidants such as vitamin E.[32] Coenzyme Q10 is not water soluble and has a large molecular weight, which makes effective absorption more difficult. Pancreatic enzymes and bile are secreted into the small intestine, which help emulsify the CoQ10 so that it can be absorbed.[33] The presence of food and lipids stimulates bile secretion, greatly increasing absorption of CoQ10, which is why CoQ10 supplements are most effective when taken with food containing fat.[33, 34] Supplements that contain solubilized CoQ10 tend to be absorbed more effectively.[33]
Through its normal metabolic processes, the human body is constantly creating free radicals — molecules that have become unstable because they are missing an electron. Free radicals cause damage to other molecules, including DNA, and those damaged molecules can then become free radicals themselves, setting off a chain of damage throughout the body. Free radicals do carry out some important functions in the body, such as fighting bacteria to prevent infections.[35, 36] However, if free radicals are not kept in proper balance with antioxidants like CoQ10, the body experiences oxidative stress and general inflammation, which can lead to cell death and illnesses such as cardiovascular disease and certain types of cancer.[6] CoQ10 and other antioxidants neutralize free radicals by giving them an electron. However, other antioxidants suffer damage in this process, whereas CoQ10 doesn’t.[1]
CoQ10 helps the body transform nutrients into energy it can use. These complex biochemical reactions depend on the help of enzymes, which are specialized protein molecules that typically require a mineral, such as zinc or magnesium, and a non-protein organic chemical, such as Vitamin B6 or CoQ10. Each cell must produce the energy it needs to function by oxidizing fats and carbohydrates and converting that energy into adenosine triphosphate (ATP), a readily usable form of energy. This is accomplished within the cell by organelles called mitochondria. Electron transport chains within the mitochondria produce ATP molecules through a series of chemical reactions.[37]
CoQ10 is particularly mobile in cell membranes due to its fat solubility, and it acts as a link between the different enzymes in the electron transport chain. The energy production process depends heavily on the presence of CoQ10 because no other substance can start the process; thus, CoQ10 is sometimes described as a biochemical “spark plug.” Without appropriate levels of CoQ10 in the mitochondria, cells would lose the ability to produce energy and would eventually die.[37]
CoQ10 Deficiency and Insufficiency
Although there is not yet an official recommended daily allowance (RDA) for CoQ10, deficiency does not seem to be widespread for healthy people.[38] It is estimated that a healthy, varied diet contributes around 25% of the CoQ10 found in blood.[39] Tissue concentrations do not always correlate with blood concentrations, so the extent to which diet contributes to CoQ10 levels in tissues is not yet fully understood.[4, 40]
The oxidative stress of smoking increases demand for CoQ10 and results in lower blood concentrations and body reserves, especially in women.[41] Lowered blood levels of CoQ10 are frequently associated with individuals with certain diseases and neurodegenerative disorders, including diabetes, congestive heart failure, cancer, fibromyalgia, and muscular and cardiovascular diseases. In certain circumstances, increasing the blood levels of CoQ10 may provide symptomatic relief for these conditions, as CoQ10 is an effective mitochondrial energizer and antioxidant.[12]
Coenzyme Q10 is synthesized in most human tissues via a three-step process involving two amino acids (either tyrosine or phenylalanine) and an enzyme called acetyl-coenzyme A. The synthesis of CoQ10 is regulated in part by another enzyme called hydroxymethylglutaryl (HMG)-CoA reductase. Vitamin B6 must be present for proper CoQ10 synthesis.[60] Deficiency in any of these CoQ10 building blocks may lead to the body producing insufficient amounts of CoQ10.
Increasing age is also a risk factor for critical CoQ10 insufficiency we are just now learning about. CoQ10 production declines naturally with age.[1] CoQ10 levels peak at about age 21 and can decrease by as much as 65% by the age of 80.[61] It has been proposed that this decline could play a role in age-associated decrease in metabolism in various parts of the body, including the liver, heart, and skeletal muscles, which can cause fatigue and potentially other complications. Currently there is no conclusive evidence that taking CoQ10 supplements will help humans live longer or prevent age-related functional declines.[1, 61] However, in rats, 12% life extension has been demonstrated possibly due to COQ10 supplementation.[71] More research is ongoing in this promising area.
Statins and CoQ10
The development of statin drugs has revolutionized our ability to treat high cholesterol and related conditions. Also known as HMG-CoA reductase inhibitors, statins reduce the action of an enzyme in the mevalonate pathway that is a major factor in the regulation of cholesterol synthesis, thereby lowering blood cholesterol to healthier levels. Unfortunately, statins may also reduce CoQ10 levels because CoQ10 synthesis is controlled by the same enzyme in the same metabolic pathway.[42, 43, 44]
This phenomenon has been studied thoroughly, and researchers have found that plasma/serum CoQ10 concentrations can be depleted by as much as 54% following statin therapy.[45, 46] The scale of the statin-induced reduction in CoQ10 levels appears to be correlated to the dose and is reversible.[47, 48] Further research is needed in order to determine whether low CoQ10 concentrations in the blood correlate with low CoQ10 concentrations in the tissues, because it is more difficult to measure CoQ10 levels in body tissues than in blood.[40, 49, 50]
One study suggests that adverse reactions to statin therapy, including the muscle symptoms associated with low CoQ10 levels, could be due to a genetic susceptibility to muscle disorders.[51] The symptoms of pain, tenderness, weakness, and fatigue that can occur in response to statin therapy may be relieved by appropriate CoQ10 supplementation.[13]
CoQ10 circulates in the blood with lipoproteins, so CoQ10 levels are dependent on levels of circulating lipids. For that reason, blood levels of CoQ10 should be checked only after total lipid or cholesterol levels have been normalized.[52, 53]
Food Sources of CoQ10
Most healthy people eating a varied diet are probably meeting their CoQ10 needs, even though it is estimated that typical dietary intake is less than 10 mg per day, and it is generally poorly absorbed.[79] However, individuals with particular health problems and those who are taking certain medications may want to increase their dietary intake with food sources that are rich in CoQ10, such as meat, poultry, fish (especially oily fish like tuna and salmon), organ meats, whole grains, and nuts. Moderate sources of CoQ10 include fruit, vegetables, eggs, and dairy products.[13, 74] The way in which these foods are cooked can have an impact on their CoQ10 content. Research has shown that when vegetables and eggs are fried, they lose between 14% and 32% of their CoQ10 content. On the other hand, when these foods are boiled, the CoQ10 content remains unchanged from their raw state.[27, 54]
CoQ10 Supplementation
Although numerous studies have shown that certain individuals can benefit from oral CoQ10 supplementation, it remains unclear whether supplementation raises CoQ10 levels in blood as well as in body tissues, or just CoQ10 levels in blood. In one study, healthy men who took 120 mg of CoQ10 supplements daily for three weeks experienced no increase in CoQ10 levels in skeletal muscle.[17, 55, 56, 57] Interestingly, however, researchers theorize that body tissues that were CoQ10 deficient may end up with higher CoQ10 levels after supplementation than tissues that had normal CoQ10 levels before supplementation.[58, 80]
In another study, patients with left ventricular dysfunction took 150 mg of CoQ10 supplements daily before cardiac surgery. After four weeks of supplementation, the plasma and cardiac tissue levels of CoQ10 had significantly increased, but supplementation had not influenced skeletal muscle concentrations of CoQ10.[59]
It is highly recommended that individuals who take statins for high cholesterol or medications for high blood sugar also take CoQ10 supplements, since those cholesterol and blood glucose-lowering medications can decrease CoQ10 levels in the body and reduce the effects of CoQ10 supplements.[60]
Because it is fat soluble, CoQ10 should be taken with a meal containing fat for maximum absorption. Even water soluble CoQ10 formulations should be taken with a meal, as this lengthens the transit time through the small intestine, creating more opportunities for absorption. CoQ10 doses that are higher than 100 mg per day should be divided into several smaller doses, as this will result in better absorption.[2, 61] Another way to increase absorption is to consume grapefruit, which is known to enhance CoQ10 absorption by as much as 150%.[62] However, people who also take statin drugs should avoid grapefruit because it impairs the body’s ability to break down statins.[62] Taking a CoQ10 supplement in the evening may also improve the body’s ability to utilize the nutrients.[13]
Proper Dosage and Contraindications
The CoQ10 dosage that doctors most commonly recommend for healthy adults is between 30 and 100 mg daily, although this is not an official Recommended Daily Allowance (RDA). In contrast, the average daily dietary intake of CoQ10 is less than 10 mg, so supplementation is thought to be beneficial in most instances.[2, 63] Therapeutic doses for people with certain medical conditions usually range from 100 to 300 mg, typically divided throughout the day because CoQ10 absorption decreases as the dose increases. Under the supervision of a medical professional, some people have taken as much as 3,000 mg of CoQ10 daily without adverse side effects.[2, 39, 64, 65] Although CoQ10 has been proven to be safe even in relatively high doses, it can cause some minor gastrointestinal symptoms such as nausea, diarrhea, loss of appetite, heartburn, and abdominal discomfort. In many cases, these symptoms can be eased by dividing the daily dose into several doses throughout the day.[13, 66, 67, 68, 64, 69]
Other mild side effects are possible, including insomnia in individuals taking 100 mg or more per day. Elevated levels of liver enzymes can occur in those taking 300 mg daily for long periods of time, although no liver toxicity has been reported. Some people may also experience rashes, dizziness, sensitivity to light, irritability, headache, or fatigue.[60]
People taking blood thinning medications such as warfarin (Coumadin) or clopidogrel (Plavix) should talk to their doctor before beginning supplementation, as studies show that CoQ10 can decrease the anticoagulant effect of these medications.[70] If they are taken concurrently, blood clotting time should be monitored frequently, especially in the first two weeks of supplementation. On the other hand, CoQ10 may improve the effectiveness of blood pressure medications, allowing some people to reduce their medication dosage, with their physician’s consent.[13, 60]
Chemotherapy patients should consult with an oncologist before supplementing with CoQ10, as its antioxidant properties could make some chemotherapy drugs less effective. Conversely, CoQ10 could help reduce damage to the heart caused by the chemotherapy drugs daunorubicin (Cerubidin) and doxorubicin (Adriamycin). People who use betaxolol (Betoptic) eye drops for glaucoma may be able to reduce the heart-related side effects without sacrificing the medication’s effectiveness by supplementing with CoQ10.[13]
Some medications may decrease levels of CoQ10 in the body and supplementation can help bring those levels back up. These drugs include: statins for cholesterol such as simvastatin (Zocor), lovastatin (Mevacor), atorvastatin (Lipitor), and pravastatin (Pravachol); labetalol (Normodyne), atenolol (Tenormin), propranolol (Inderal), metoprolol (Lopressor or Toprol), and other beta blockers for high blood pressure; gemfibrozil (Lopid) and other fibric acid derivatives for cholesterol; and tricyclic class antidepressants including amitriptyline (Elavil), imipramine (Tofranil), and doxepin (Sinequan).[13]
Choosing A CoQ10 Supplement
One of the reasons that CoQ10 is so vital to the human body is its ability to switch back and forth between two different forms, depending on what the body needs.[2] Ubiquinone (the oxidized form of CoQ10) is fat soluble and is not very bioavailable as a supplement unless it has added ingredients, such as an emulsifier. However, it was the only form of CoQ10 on the market until 2006, when ubiquinol (the reduced form) became available.[1] Because it is water soluble, ubiquinol is up to eight times more absorbable than ubiquinone.[72, 73]
Regardless of which form you take, CoQ10 will eventually change into whichever form the body needs at a particular moment. It becomes ubiquinol in the blood and lymph in order to perform its antioxidant duties, while in the mitochondria it switches rapidly back and forth as needed between ubiquinol and ubiquinone to support energy metabolism.[74, 1] Color is a useful clue to help identify whether a CoQ10 supplement contains ubiquinol or ubiquinone. Ubiquinol is milky white while ubiquinone is yellowish. It is worth noting that ubiquinol is susceptible to oxidation and, under certain conditions, can become ubiquinone right in the bottle.[1] Because it is unstable and easily converts to ubiquinone, ubiquinol costs more to manufacture and thus costs more for consumers to purchase. Most experts agree that the bioavailability of the product, or its final ability to be absorbed, is far more important than the form (ubiquinone vs. ubiquinol).[1, 82, 83]
Some CoQ10 products also contain shilajit, a natural material exuded from rocks in mountain ranges around the world. It has been used for medicinal purposes for thousands of years in Ayurveda (traditional Indian medicine). Modern research has verified its antioxidant and anti-inflammatory properties, as well as its ability to stabilize physiological processes, regulate the immune system, and normalize blood lipid levels.[75, 76] Some research suggests that the body will make better use of a supplement when CoQ10 and shilajit are taken together.[77, 78]
Most CoQ10 products are created through yeast fermentation, which produces a raw material that has the same molecular structure as the CoQ10 synthesized by the human body. Yeast fermentation yields a product that is free of unknown impurities and the unsafe cis isomers found in synthetic CoQ10.[1, 83] Furthermore, synthetic CoQ10 supplements are more expensive to manufacture and are therefore difficult to find.
Products that consist of unprocessed CoQ10 crystals have an absorption rate of less than 1% because the crystals begin to melt only when they reach 118.4 degrees F (48 degrees C). They cannot be absorbed by the digestive tract until they are broken down into individual molecules.[1]
The cost of CoQ10 supplements can vary significantly, as manufacturers try to find the most suitable and cost-effective way to increase bioavailability. Consumers can purchase CoQ10 supplements in a variety of different formulations, including oral spray, hard shell capsules, tablets, and softgels. Softgels seem to facilitate the most absorption and therefore the most benefit. However, it is worth keeping in mind that intestinal absorption of CoQ10 can vary significantly among different individuals.[81, 82]