Coenzyme Q10, because of its ubiquitous properties, also known as ubiquinone, participates in energy production, but also fights free radicals, accelerates metabolism, slows down aging, can be called rejuvenation nutrients. Note 19
Although coenzyme Q10 is structurally similar to some vitamins (e.g. vitamin K), it is not a vitamin because it can be synthesized in the body (mainly in the inner mitochondrial membrane), and the vitamin must be obtained from the diet.
Because it can be synthesized in all tissues, the body is not usually dependent on the exogenous supply of coenzyme Q10. However, endogenous biosynthesis tends to decline with age.
In addition, tissue coenzyme Q10 may be impaired in many pathophysiological states. In this case, supplementation with exogenous coenzyme Q10 may be required to maintain normal blood and tissue levels.
What are the benefits of CoQ10 in empirical medicine? Are there side effects of CoQ10? For details, please refer to the latest empirical discussion in the text
What is Coenzyme Q10?
Coenzyme Q10 is a benzoquinone compound (structurally similar to vitamin K) that was first isolated from bovine heart mitochondria in 1957 by Frederick Crane of Wisconsin, USA. The identification and synthesis of the chemical structure was completed in 1958.
Coenzyme Q is a naturally occurring coenzyme, present in tissues and cells of all species, mainly located in the inner mitochondrial membrane, is composed of benzoquinone ring combined with hydrophobic isoprenoid chain, the length of the side chain varies from species to species (Saccharomyces cerevisiae is mainly CoQ6), in human mitochondria, coenzyme Q mainly contains 10 isoprene groups, so it is named coenzyme Q10.
Coenzyme Q10 (CoQ10) is synthesized primarily in the inner mitochondrial membrane, with a small portion obtained through the diet.
What are the characteristics of CoQ10?
Coenzyme Q10 plays an important intermediary role in the mitochondrial electron transport chain and is mainly involved in adenosine triphosphate (ATP) synthesis, which provides energy for muscle contraction and other important cellular functions, and therefore affects all cells, especially those with high energy needs, such as the heart, lungs, liver, kidneys, spleen, pancreas and adrenal glands, which is extremely important for health.
When it is reduced, CoQ10 is also an important lipid antioxidant in the body, reducing free radical production and preventing protein, lipid and DNA oxidation.
In addition, coenzyme Q10 can inhibit the cytokines TNF-α and NF-κB associated with inflammation, and affect the expression of hundreds of genes related to metabolism and transport.
What are the food sources of CoQ10?
Coenzyme Q10 is abundant in animal sources, including beef, poultry, pork liver, eggs, and fatty fish such as mackerel, salmon, salmon, and tuna.
Plant sources include: nuts, oranges, strawberries, spinach, cauliflower, broccoli, lentils, soybeans, etc.
The study pointed out that whether it is taken from food or health products, the absorption rate of the two is actually not much different. Note 16
What are the proven benefits of coenzyme Q10?
Coenzyme Q10 is beneficial to blood lipid regulation
Dyslipidemia impairs mitochondrial function, leading to increased production of free radicals and reactive oxygen species, leading to chronic inflammation and endothelial dysfunction
The study found that patients over the age of 65 had a high incidence of hyperlipidemia, with total cholesterol levels exceeding 25 mg/dL in about 42% of men and 240% of women
A systematic literature review and meta-analysis (21 randomized controlled trials involving 1039 participants with metabolic diseases) noted that coenzyme Q10 supplementation (daily doses between 100 and 300 mg) significantly reduced triglycerides levels, but was not significantly helpful in improving total cholesterol, LDL, and HDL cholesterol levels. Note 1
*Conclusion: For patients with metabolic diseases, coenzyme Q10 supplementation may bring positive help to blood lipid regulation (especially triglycerides), but more studies are still needed for further verification
Coenzyme Q10 improves physical activity-related fatigue
Fatigue is a pervasive symptom of daily life and is often described as a lack of energy, decreased endurance, and the need for a long period of recovery (whether mental or physical) after physical activity.
Fatigue affects everyone, regardless of their skills, knowledge, and training status.
In the workplace, the most important effects of fatigue include decreased motivation, prolonged reaction times, decreased alertness, poor concentration, poor psychometric coordination, memory and information processing problems, and poor judgment.
A double-blind, placebo-controlled study (8-day study of 17 healthy subjects) noted that oral administration of CoQ10 helped improve maximal velocity change after fatigue-induced physical tasks. Note 1
In addition, subjects given CoQ10 (dose 300 mg) had lower subjective fatigue sensation and recovery period than placebo.
*Conclusion: Oral administration of Coenzyme Q10 may improve fatigue and performance associated with physical activity
Coenzyme Q10 is beneficial to vascular endothelial function
Vascular endothelium is an active monolayer of cells that cover the lumen of blood vessels, separating the vascular wall from circulating blood, and is also a highly selective barrier and metabolically active organ, which is of great significance for hemostasis and thrombosis, regulation of local vascular tone and redox balance, coordination of acute and chronic inflammatory reactions within the arterial wall.
There is growing evidence that endothelial cell dysfunction is the first recognizable sign of atherosclerosis development and that it existed long before atherosclerotic cardiovascular disease occurred.
A meta-analysis (5 randomized controlled trials with 194 participants) showed that coenzyme Q10 significantly improves endothelial function through flow-mediated dilation. Note 1
However, the fixed-effect model assessing endothelial function by nitrate-mediated dilatation of arteries did not significantly improve.
*Conclusion: Coenzyme Q10 supplementation may have a positive effect on the improvement of vascular endothelial function, but whether it can reduce the risk of cardiovascular disease remains to be confirmed
Coenzyme Q10 can help lose weight
Obesity is the abnormal accumulation of body fat (usually 20% higher than the normal ideal weight), and affected people are also vulnerable to discrimination, even low self-esteem and depression, in personal and working life due to the psychological and social stigma that accompanies overweight and obesity.
In addition, depending on the degree, duration, and distribution of overweight, excess weight can progressively cause or exacerbate a variety of comorbidities, including type 2 diabetes, high blood pressure, dyslipidemia, cardiovascular disease, nonalcoholic fatty liver disease, reproductive dysfunction, breathing abnormalities, psychiatric disorders, and even an increased risk of certain cancers.
A systematic literature review and meta-analysis (including 17 randomized controlled trials) showed that CoQ10 supplementation had no significant effect on body weight (weighted mean difference WMD: 0.28 kg) and body mass index (weighted mean difference WMD: -0.03). Note 1
In addition, subgroup analysis showed that Q10 dose and trial duration had no effect on supplementation results.
*Conclusion: To date, there is no evidence that CoQ10 supplementation is helpful for weight loss, but limited by the heterogeneity of the included studies, more studies are needed to confirm its clinical benefit
Coenzyme Q10 improves disease-related fatigue
Fatigue is one of the most common complaints in physician consultations and is characterized by reduced ability to work or motivation, often accompanied by feelings of tiredness and drowsiness.
This type of fatigue is a nonspecific symptom associated with many conditions, such as hypothyroidism, celiac disease, anemia, influenza, heart failure, acute liver disease, cancer, diabetes, and sleep apnea.
A randomized, double-blind, placebo-controlled study (24 weeks in 236 breast cancer patients undergoing chemotherapy) found that oral CoQ10 did not improve self-reported fatigue or quality of life scores. Note 2
Another randomized, double-blind, placebo-controlled study (12-week study of 48 patients with multiple sclerosis) showed that oral coenzyme Q10 (500 mg daily) improved fatigue and depression. Note 3
*Conclusion: For the improvement of disease-related fatigue, the results of using coenzyme Q10 (coenzyme Q10) are mixed and need to be confirmed
Coenzyme Q10 is beneficial for blood sugar control
Type 2 diabetes mellitus was considered a rare disease 30 years ago, but in recent decades, Asia has experienced rapid economic development, urbanization and a shift in nutritional status, resulting in a massive increase in obesity and diabetes, about 2% of the global diabetic population.
Adults with diabetes have a 50% higher risk of dying from all causes than adults without diabetes, in addition to the risk of various complications (including accelerated progression of cardiovascular disease, end-stage renal disease, vision loss and amputation).
A systematic literature review and meta-analysis (13 randomized controlled trials, 765 patients with type 2 diabetes) suggested that oral administration of CoQ10 improved glycaemic control (lowering glycosylated hemoglobin, fasting blood glucose) and lipids (lowering triglycerides, increasing HDL cholesterol). Note 4
*Conclusion: For type 2 diabetes, oral coenzyme Q10 has a positive effect on glycemic control, but more studies are needed to support it due to possible risk bias and heterogeneity
Coenzyme Q10 is beneficial for migraines
Migraine is the second most common headache and is usually described as moderate to severe unilateral pain with repeated throbbing or pulsating, usually lasting 4-72 hours, and may be accompanied by nausea, vomiting, or sensitivity to light, sound, or smell.
Before a migraine attack, about one-third of patients can feel aura, most commonly visual aura, in the form of jagged lines or scattered flashing dark spots (lasting about 5-60 minutes).
A meta-analysis (5 studies, 346 migraine patients) showed that oral coenzyme Q10 reduced the number of days/month and duration of attacks compared with placebo, but there was no significant change in severity/day and attacks/month. Note 5
*Conclusion: Coenzyme Q10 has a positive effect on migraine improvement, but limited by the small sample size, more large trials are still needed for further verification
Coenzyme Q10 is beneficial for sarcopenia
Sarcopenia is an age-related senile syndrome characterized by skeletal muscle loss, reduced muscle strength, decreased physical performance, etc., increasing the risk of osteoporosis, obesity, and type 2 diabetes, with a prevalence of 5% to 10% in people over 65 years of age.
Sarcopenia causative factors are associated with decreased calorie intake, inadequate blood flow to muscles, mitochondrial dysfunction, decreased anabolic steroids, and increased pro-inflammatory cytokines.
In population observational studies, low CoQ10/cholesterol ratio and reduction state CoQ10 levels can be considered important indicators of sarcopenia (poor upper body muscle strength, muscle mass, and peak expiratory flow). Note 6
*Conclusion: Low levels of coenzyme Q10 are considered to be an indicator of sarcopenia, but more research is needed to confirm whether supplementation can bring benefits
Coenzyme Q10 improves inflammatory indicators
Inflammation is a physiological response of biological tissues to injury, pathogen invasion, or irritants, mainly manifested as temperature rise, redness, swelling, and pain caused by increased local blood flow.
While short-term or acute inflammation is a unique protective reflection of the organism to eliminate harmful irritants and initiate self-healing mechanisms, long-term or chronic inflammation is considered to be the main factor leading to a variety of chronic diseases, such as cardiovascular disease, chronic kidney disease, type 2 diabetes, chronic obstructive pulmonary disease, and cancer.
A systematic literature review and meta-analysis (including 17 randomized double-blind controlled studies) found that CoQ10 supplementation had significant effects on C-reactive protein, interleukin-6 (IL-6), and tumor necrosis factor (TNF-α). Note 7
The mechanism behind this may be related to the capture of free radicals by coenzyme Q10 and the inhibition of nuclear transcription factor (NF-κB) activation.
*Conclusion: Coenzyme Q10 supplementation (Coenzyme Q10) has the effect of reducing a variety of pro-inflammatory hormones, but due to high heterogeneity between studies, more evidence is needed
Coenzyme Q10 is beneficial for heart failure
Cardiac failure often occurs when the ventricles are unable to pump blood efficiently (systolic dysfunction) and relaxation is impaired (diastolic dysfunction), and may be characterized by abnormal gasping during exercise or rest, fatigue, or swollen ankles.
Heart failure is often associated with coronary heart disease, hypertension, cardiomyopathy, aging, and valve abnormalities, but congenital heart disease is the most common.
A meta-analysis (14 randomized controlled trials, 2149 patients with heart failure) noted that the use of coenzyme Q10 reduced mortality by 31% and improved exercise capacity compared with placebo (although there was no significant difference between left heart ejection fraction and NYHA classification of the New York Heart Association). Note 8
*Comment: Coenzyme Q10 can reduce mortality and improve exercise capacity in patients with heart failure, but it is limited by possible bias and heterogeneity, and needs to be confirmed by more rigorous and large sample experiments
Coenzyme Q10 is beneficial for male infertility
At present, most developed countries are facing serious fertility decline, which is caused by complex social and environmental factors, including economic development, environmental pollution and climate warming.
Age is also a cause of infertility, with a population survey showing that men are 30% less likely to get their partner pregnant after age 40 (compared to age 30). Note 9
A meta-analysis (3 studies, 296 participants) found that although oral coenzyme Q10 (CoQ10) increased sperm concentration and motility, its effect on improving live birth or pregnancy rates is unknown. Note 10
*Conclusion: Coenzyme Q10 can improve the relevant conventional semen parameters, but there is no evidence to increase the chance of pregnancy, and other experiments need to be verified
Coenzyme Q10 is beneficial to high blood pressure
Primary hypertension is the most common blood pressure disease (about 90% to 95%), although there is no direct cause, but it is related to a variety of life factors, such as sedentary, stress, visceral obesity, overweight, alcohol intake, aging…
Coenzyme Q10 is believed to be beneficial for blood pressure control due to its antioxidant properties, improving vascular endothelial function, reducing peripheral resistance and inhibiting peroxide production.
A Cochrane Review (2 randomized controlled studies) found that oral CoQ10 did not produce clinically significant blood pressure lowering effects (systolic blood pressure drop of 3.68 mm, diastolic blood pressure drop of 2.03 mm Hg) compared with placebo. Note 11
*Conclusion: Although coenzyme Q10 has the effect of lowering blood pressure, it does not meet the clinically significant standard, and more large-scale controlled studies need to further verify
Coenzyme Q10 is beneficial for polycystic ovary syndrome
Polycystic ovary syndrome is the most common endocrine disorder in women of reproductive age, with a prevalence of about 5-21%.
Patients often present with symptoms such as reproductive dysfunction (hyperandrogens, hirsutism, cessation of ovulation, infertility, menstrual disorders), metabolic system abnormalities (obesity, diabetes, and cardiovascular disease), and mood disorders.
It has also been clinically found that more than half of patients will have hyperinsulinemia and dyslipidemia, which greatly increases the risk of cardiovascular disease. Note 12
A double-blind controlled study (12 weeks, 60 women with PCOS) supplementation with CoQ10 (100 mg daily) helped improve glycaemic metabolism (fasting blood glucose and insulin-related values), total cholesterol, and LDL cholesterol, which may have a beneficial effect. Note 13
*Conclusion: Coenzyme Q10 may have a positive effect on improving polycystic ovary syndrome, which needs to be further verified by more large controlled studies
Coenzyme Q10 improves Parkinson’s disease
Parkinson disease is caused by the degeneration of the substantia nigra striatum associated with the nerve conduction substance: dopamine, which makes it difficult to transmit instructions to the brain, resulting in motor dysfunction, but the brain’s memory and cognitive functions can function normally.
Although Parkinson’s disease does not necessarily evolve into dementia, 61% of patients experience psychiatric symptoms, including depression, anxiety, hallucinations, and sleep disturbances.
Relevant studies have pointed out that Parkinson’s patients are about 4 to 5 times more likely to be deficient in coenzyme Q10 than normal people. Note 14
But to date, a systematic review (5 randomized controlled trials with 981 participants in Parkinson’s patients) and meta-analysis have found that CoQ10 supplementation does not confer any benefit or slow functional deterioration. Note 15
*Conclusion: Coenzyme Q10 is not significantly helpful in improving Parkinson’s disease
Are there any side effects of CoQ10?
Most adults are safe for oral administration of Coenzyme Q10 at doses up to 3,000 mg per day (Note 20) for 8 months; 1200 mg per day for 16 months (Note 21); 600 mg per day for 30 months (Note 22), no significant side effects were reported.
Mild side effects reported include: stomach upset, allergic rash, loss of appetite, nausea, heartburn, vomiting, insomnia, fatigue, dizziness, light sensitivity, irritability, and diarrhea (especially at doses up to 200 mg per day).
1. During pregnancy, it is safe to start taking coenzyme Q10 after about 20 weeks of pregnancy; However, the safety of lactation is still unknown, so it is recommended not to use it
2. Do not use with chemotherapy drugs: alkylating agents, coenzyme Q10 may reduce the effectiveness of these drugs, related drug names are: busulfan, carboplatin, cisplatin, cyclophosphamide, dacarbazine, Thiotepa (Titipa)
3. Coenzyme Q10 may have a blood pressure-lowering effect, so patients with low blood pressure or those taking antihypertensive drugs should use it with caution, related drugs are: captopril, enalapril, losartan, valsartan, diltiazem, amlodipine, Hydrochlorothiazide, furosemide
4. Discontinue use two weeks before scheduled surgery, as coenzyme Q10 may affect blood pressure control during and after surgery.
5. Do not use it in combination with the anticoagulant Warfarin, because coenzyme Q10 helps coagulation, if used together, it will reduce the effectiveness of the drug, if you need to use warfarin and coenzyme Q10 at the same time, be sure to take regular blood tests to assess clotting time, especially in the first two weeks.
6. Taking it before bed may cause insomnia, so it’s best to take it in the morning or afternoon
How is CoQ10 taken? What is the dose?
Standard doses of CoQ10 range from 90 mg to 200 mg per day, and needs may vary depending on the person and situation being treated, with some studies using even higher doses.
Because CoQ10 is a fat-soluble compound, its absorption is slow and limited when used on an empty stomach. Therefore, it is recommended to take it with meals to speed up absorption.
Experiments have found that if ingested with fatty foods, intestinal absorption can be accelerated by 3 times. Note 17
What are the dosage forms of CoQ10?
In humans, there are two different forms of CoQ10, the reduced form ubiquinol, which makes up 10% of CoQ90 in the blood.
Both forms are helpful in increasing circulating levels of CoQ10 in the body.
In a study comparing the two forms separately, plasma concentrations of ubiquinol increased by 4.77 times after 4 weeks of use, compared to 2.77 times that of ubiquinone, which showed that the bioavailability of ubiquinol was significantly higher (about 1.72 times higher, but relatively, the price of related supplements was also more expensive). Note 18