What is Coenzyme Q10 (CoQ10) and what does it do?
Coenzyme Q10 (CoQ10) is a fat soluble compound synthesized in the body. It is commonly referred to as ubiquinone because it is found in almost every cell in all living organisms, making it ubiquitous in nature. CoQ10 is found in the mitochondrial membrane where it helps convert food to ATP, the energy used by cells.1 More specifically, it converts carbs and fats to ATP by delivering electrons to oxygen as part of the electron transport chain in the final steps of fatty acid and glucose metabolism.1 Therefore, CoQ10 is an essential component of energy production.
Due to its essential role in mitochondrial energy production, it affects the function of all cells, especially those with high energy demands like the heart, kidneys, muscles, and brain.2 CoQ10 also plays a role in carbohydrate metabolism, immune health and cardiac function.2 Additionally, it acts as a powerful antioxidant that protects cell membranes and lipoproteins (the particles that carry cholesterol in the bloodstream) from oxidation.2 It helps neutralize free radicals and regenerate antioxidants like vitamin E and vitamin C, ultimately supporting the immune system and reducing inflammation.1
What is the Recommended Dietary Allowance (RDA) for CoQ10?
CoQ10 is synthesized in most human tissues, even when we aren’t eating CoQ10. Since the body makes CoQ10 on its own, an RDA has not been established for daily intake. In those with genetic conditions, CoQ10 synthesis may be impaired and dietary intake and supplementation would be required to maintain adequate energy production.
Food Sources of CoQ10
It’s unclear how dietary intake contributes to tissue CoQ10 concentrations, although it’s believed to contribute to about 25% of plasma CoQ10.1 Since foods rich in CoQ10 tend to be very nutrient dense, it can’t hurt to prioritize their intake on a regular basis. Some rich sources of CoQ10 include:
- Rainbow trout
- Sesame seeds
What are the different forms of CoQ10?
The two main forms of CoQ10 supplements are ubiquinone and ubiquinol. Ubiquinone is the oxidized form of CoQ10 and the most widely available and researched form used in supplements. The body has to convert ubiquinone into ubiquinol for it to be useful in cellular energy production. Ubiquinol is the reduced, active antioxidant form of CoQ10. It is more bioavailable, meaning it gets absorbed better into the bloodstream and is more readily used by the body’s cells. Ubiquinol also acts as an antioxidant, meaning it can neutralize harmful free radicals in the body, while ubiquinone does not have this property to the same extent. However, ubiquinol supplements are usually more expensive than ubiquinone supplements. Ubiquinone is also generally more stabile than ubiquinol, which can oxidize and turn back into ubiquinone when exposed to air or light. This is less relevant for pediatric patients, but it should be noted that as we age the body’s ability to convert ubiquinone to ubiquinol may decrease, making ubiquinol a more attractive option for older adults.
What are the signs of CoQ10 deficiency?
Since CoQ10 is central to ATP production, even mild deficiencies can impair the electron transport chain and energy production, ultimately impairing most bodily processes like immunity, digestion, and function of energy demanding organs like the heart, brain, and kidney.1 Early signs of a deficiency include fatigue and muscle weakness, while a prolonged deficiency can result in organ damage, brain inflammation, hearing loss, and cognitive impairment.
Numerous medications can contribute to a CoQ10 depletion, including statins, diabetic medications, beta-blockers and tricyclic antidepressants. Other causes include poor dietary intake, myalgia, high blood pressure, periodontal disease, immune related conditions, and mitochondrial myopathy.1 Serum CoQ10 assessments are widely available to determine a deficiency. Organic acid testing for hydroxymethylglutarate (HMG) and urinary tests for lactate, succinate, fumarate, and malate can be performed to further assess CoQ10 status. Elevated urinary HMG is especially indicative of poor synthesis of CoQ10. Clinically I often see elevated HMG in some (but not all) children with autism, as well as many adults and teens with Chronic Fatigue Syndrome/Myalgic Encephalitis.
Genetic disorders resulting in primary CoQ10 deficiency do occur in rare instances. Oral supplementation can improve muscular symptoms in some patients with primary CoQ10 deficiency, but the neurological symptoms are harder to treat.1 CoQ10 concentrations appear to decline with age and other conditions like diabetes, cancer, and congestive heart failure.1
Is CoQ10 supplementation safe?
No significant adverse effects have been reported following CoQ10 supplementation.1 Doses up to 1,200 mg/day are considered safe but higher ranges should be monitored by a medical provider. Mild side effects include GI discomfort like nausea, diarrhea, heartburn, and abdominal pain.1 Allergic rash and headache have also been reported.3 Taking smaller doses divided throughout the day may reduce the risk of side effects.
CoQ10 has antiplatelet effects that can increase the risk of bleeding and thus should be taken with extreme caution if the patient is also on warfarin or other blood thinning medications. In some cases the dose of warfarin may need to be adjusted. In other cases CoQ10 should not be taken at all.
Clinical uses of CoQ10 in naturopathic medicine
It is important to note that naturopathic physicians rarely – if ever – prescribe a single therapy for any given condition. Research shows a role for CoQ10 in the following conditions. However, in clinical practice I typically use CoQ10 in conjunction with additional supplements, diet and lifestyle changes to achieve the desired outcome.
Chronic Fatigue Syndrome
Chronic Fatigue Syndrome (CFS) is characterized by severe and ongoing fatigue for at least six months. The cause remains unknown and few treatments have proven effective. Studies indicate a correlation between CFS, oxidative stress, and mitochondrial dysfunction. CoQ10 has been used to support cellular ATP production to ease the fatigue associated with CFS.4 Additional studies suggest that a combination of CoQ10 and NADH can improve endothelial function and the perception of fatigue in those with CFS.4 Other studies indicate less significant results, but due to the low risk associated with CoQ10 supplementation, it may be a viable consideration in those struggling with CFS.
For some people, migraines are the result of abnormal mitochondrial energy production. In these cases, pharmacological doses of riboflavin (B2) and CoQ10 can be a safe and effective prophylactic treatment for migraines.3 In fact, one study found 150 mg/day of CoQ10 for three months cut the number of migraine days in half!3 Additionally, there may be an association between low CoQ10 and pediatric and adolescent migraines.3 Testing for a deficiency is recommended in these cases and supplementation can be determined by a pediatrician or licensed nutritionist.
Cyclical vomiting syndrome
Cyclic vomiting syndrome (CVS) is a condition characterized by recurrent episodes of nausea and vomiting. CVS is often associated with migraines based on their overlapping symptoms like headache,
nausea, and light sensitivity, as well as the underlying mitochondrial dysfunction.5 Although the studies are limited, CoQ10 appears to be a well tolerated and effective treatment for CVS.5
Autism Spectrum Disorder
Autism Spectrum Disorder (ASD) has also been associated with mitochondrial dysfunction and abnormalities in carbohydrate metabolism.6 Elevations of lactate and pyruvate are significantly more common in children with ASD, suggesting a breakdown in carb metabolism and energy production. Treatment studies are limited, but some suggest CoQ10, as well as B vitamins and carnitine can help improve the symptoms of mitochondrial dysfunction in those with ASD.6 Another study found CoQ10 supplements reduced markers of oxidative stress, increased total antioxidants, and improved sleep and gastrointestinal problems in children with ASD.7 Oxidative stress and mitochondrial dysfunction are quite prevalent in those with ASD and CoQ10 supplements may be an additional tool to mitigate the associated symptoms.
Diabetes is a metabolic disorder associated with abnormal carbohydrate metabolism and a high degree of oxidative stress.3 CoQ10 levels are typically decreased in this population but are reversible with adequate supplementation. Studies show that 200 mg/day of CoQ10 can improve endothelial function, decrease blood pressure, decrease HbA1C and improve nerve conduction associated with peripheral neuropathy in type 2 diabetes.3
Periodontal disease is an inflammatory disease caused by bacteria infecting the gums, resulting in swollen, red, and bleeding gums3. CoQ10 has been found to effectively suppress periodontal inflammation via its potent antioxidant effect.3
Optimizing pregnancy outcomes
During pregnancy, CoQ10 plasma levels rise throughout each trimester.3 Low levels are associated with fetal wasting, spontaneous abortion, and an increased risk of preeclampsia in women in the high risk category.3 If you’re concerned about your CoQ10 levels, consult with your physician and consider assessing and supplementing accordingly.
Down syndrome is a chromosomal disorder that is associated with both structural and functional abnormalities.3 Two small studies have found CoQ10 treatment to improve antioxidant efficacy and modulate DNA repair mechanisms.3
Other (cardiovascular conditions and aging):
Much of the research into CoQ10 involves studies in adults, and is well beyond the scope of this article focusing on pediatric conditions. We will summarize briefly just for context.
CoQ10 has been studied in various cardiovascular conditions, including heart failure and atherosclerosis. In heart failure, CoQ10 supports energy production in the heart, enhances cardiac contractility, and reduces endothelial dysfunction.3 Furthermore, its antioxidant activity and ability to prevent LDL oxidation improves the quality of life in cardiac patients.3 In atherosclerosis, CoQ10 inhibits the peroxidation of cell membrane lipids in the bloodstream and has an anti-atherogenic effect.3 Supplemental doses of 150 mg/day have been found to decrease oxidative stress, increase antioxidant activity, and decrease inflammatory markers like IL-6 in patients with atherosclerosis.3
CoQ10 is implicated in aging populations due to its antioxidant effects and role in energy production in high demand tissues like the heart and brain3. Early research suggests supplementing with CoQ10 to enhance health during the aging process.3
CoQ10 is a widely available supplement, with doses ranging from 30-100 mg/day.1 Larger doses (>100 mg/day) are typically divided throughout the day to increase absorption. Orally administered CoQ10 is poorly absorbed with approximately 5% reaching circulation.1 CoQ10 in ubiquinol form may be better absorbed. However, individuals with CoQ10 deficiency may require large pharmacological doses to relieve their symptoms. Since CoQ10 is fat soluble, absorption is increased when it’s taken with a meal containing healthy fats like avocado, olive oil, or fish. CoQ10 is also somewhat pricey, and doses in the 400+ mg range often top $75 or more for a 30-day supply. Be wary of cheap CoQ10 supplements, as the quality is likely suspicious.
Summary of CoQ10
CoQ10 is a fat soluble compound synthesized by most tissues in the human body. It plays a critical role in energy production, especially for energy demanding organs like the heart, brain, kidneys, and muscles. CoQ10 is also a strong antioxidant that supports the regeneration of other antioxidants like vitamin E and C, promotes immune health, and protects cell membranes and lipoproteins from oxidation. Since the body synthesizes CoQ10 on its own, there aren’t established daily requirement, but eating a well rounded diet rich in whole foods is a great way to ensure optimal CoQ10 status.
CoQ10 supplements are generally safe and well tolerated. They are helpful in conditions associated with mitochondrial dysfunction and inflammation like Chronic Fatigue Syndrome, migraines, cyclical vomiting syndrome, Autism Spectrum Disorder, diabetes, periodontal disease, down syndrome, and cardiovascular conditions. Assessment of CoQ10 by urinary organic acids can help determine the necessity of supplementation.
- Higdon J. Coenzyme Q10. Linus Pauling Institute, Oregon State University. 2003.
- Zakkaria L. Conditionally Essential Nutrients. University of Bridgeport. 2021.
- Garrido-Maraver J, Cordero MD, Oropesa-Avila M, et al. Clinical applications of coenzyme Q10. Front Biosci (Landmark Ed). 2014;19(4):619-633. Published 2014 Jan 1. doi:10.2741/4231.
- Testai L, Martelli A, Flori L, Cicero AFG, Colletti A. Coenzyme Q10: Clinical Applications beyond Cardiovascular Diseases. Nutrients. 2021;13(5):1697. Published 2021 May 17. doi:10.3390/nu13051697
- Boles RG, Lovett-Barr MR, Preston A, Li BU, Adams K. Treatment of cyclic vomiting syndrome with co-enzyme Q10 and amitriptyline, a retrospective study. BMC Neurol. 2010;10:10. Published 2010 Jan 28. doi:10.1186/1471-2377-10-10
- Rossignol DA, Frye RE. Mitochondrial dysfunction in autism spectrum disorders: a systematic review and meta-analysis. Mol Psychiatry. 2012;17(3):290-314. doi:10.1038/mp.2010.136
- Mousavinejad E, et al. Coenzyme Q10 supplementation reduces oxidative stress and decreases antioxidant enzyme activity in children with autism spectrum disorders. Psychiatry Research. 2018. 265;62-69.