Coenzyme Q10

Coenzyme Q10 (COQ10) is a molecule produced in the body. It aids mitochondria during energy production and is a part of the endogenous antioxidant system. It is similar to other pseudovitamin compounds because it is vital for survival, but does not necessarily need to be taken as a supplement. However, there is a potential for deficiency due to suffering a heart attack, taking statins, various disease states, and aging.

It is found in various foods; mainly meat and fish.

Some research suggests minor improvements in the function of blood vessels, leading to reduce blood pressure and improved blood flow. However, more studies are needed to confirm this. The proposed mechanism is related to nitric oxide preservation, as seen with grape seed extract, pycnogenol, and resveratrol.

It seems to be strongly effective for reducing the symptoms of fibromyalgia, but this is based on a handful of small studies, and much more research is needed to confirm this.

It seems to be safe but more research is needed to evaluate its safety in the long-term. In animals, a massive dose of 350mg/kg body weight has been observed to exacerbate the effects of aging, but human studies don't suggest any convincing adverse effects from normal doses.

The standard dose for CoQ10 is generally 90mg for a low dose and 200mg for the higher dose, taken once daily with a meal due to its reliance on food for absorption. Dose-dependence is not commonly observed with CoQ10 supplementation and 90mg tends to be the best cost-effective dose.

There generally isn't too much of a therapeutic effect of CoQ10 supplementation (mostly taken with the 'just in case' mentality that pervades multivitamin supplementation), although for people who have previously experience a heart attack or damage to cardiac tissue as well as for people on statin therapy supplementation becomes much more important.

CoQ10 supplements can be either the oxidized form (ubiquinone) or reduced form (ubiquinol) as both forms seem pretty equally potent in increasing circulating levels of total CoQ10 in the body. 'Total CoQ10' refers to the sum of both forms, since CoQ10 can readily swap between forms as it acts in the body.

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what effects coenzyme q10 has on your body, and how strong these effects are.

Grade	Level of Evidence [show legend]
	Robust research conducted with repeated double-blind clinical trials
	Multiple studies where at least two are double-blind and placebo controlled
	Single double-blind study or multiple cohort studies
	Uncontrolled or observational studies only

Level of Evidence ? The amount of high quality evidence. The more evidence, the more we can trust the results.	Outcome	Magnitude of effect ? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.	Consistency of research results ? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.	Notes
	Lipid Peroxidation	Notable	Very High See all 4 studies	Appears to reduce biomarkers of lipid peroxidation. CoQ10 tends to be a reference drug for lipid peroxidation, and although it is more potent than other nutraceuticals it is not astounding.
	Blood Flow	Minor	Very High See all 3 studies	Appears to increase blood flow in metabolic conditions characterized by both insufficient blood flow and an excess of oxidative stress.
	Blood Pressure	Minor	Low See all 6 studies	There appears to be an interaction between CoQ10 and blood pressure, but it is not wholly reliable and uncertain whether this is at the level of the cardiac tissue or at the level of the endothelium (both plausible). Magnitude of reductions don't appear too remarkable.
	Endothelial Function	Minor	Very High See all 5 studies	The effective size does not appear to be overly large, but CoQ10 is associated with a protective effect on blood flow and endothelial function in persons with otherwise impaired function.
	Exercise Capacity (with Heart Conditions)	Minor	Very High See all 4 studies	Appears to aid exercise capacity in persons after myocardial infarction
	Exercise-Induced Oxidation	Minor	Moderate See all 4 studies	Mixed effects on exercise-induced oxidation, but there appears to be some potential for CoQ10 supplementation to reduce oxidation.
	Fatigue	Minor	High See all 3 studies	There may be an anti-fatigue effect of CoQ10 during exercise that may not extend to general fatigue.
	General Oxidation	Minor	High See all 6 studies	Appears to generally reduce pro-oxidative biomarkers in the body
	HbA1c	Minor	Low See all 3 studies	There may be an effect on HbA1c, but it appears unreliable and not overly potent.
	Inflammation	-	High See all 3 studies	Classical inflammatory cytokines do not appear to be altered much following CoQ10 supplementation, although there may still be a minor antiinflammatory effect
	Symptoms of Fibromyalgia	Strong	Very High See all 5 studies	CoQ10 appears to be quite strongly effective for reducing symptoms of fibromyalgia (strong rating may be retracted at a later time when other reference drugs arise)
	Symptoms of Peyronie's Disease	Notable	- See study	Notable reduction in the progression of Peyronie's disease state (and secondary to that, improvements in erectile properties) as CoQ10 may be one of the only oral treatments of this condition
	Anti-Oxidant Enzyme Profile	Minor	Moderate See 2 studies	May increase levels of antioxidant enzymes, does not appear to be reliable
	Erections	Minor	- See study	Increased erectile function has been noted with CoQ10, but this may be secondary to reductions in symptoms of Peyronie's Disease
	Follicle-Stimulating Hormone	Minor	- See study	A decrease in follicle stimulating hormone has been detected
	Luteinizing Hormone	Minor	- See study	A decrease in luteinizing hormone has been detected with CoQ10 supplementation
	Migraine	Minor	- See study	Degree of improvement is not overly remarkable, with portions of the trial not outperforming placebo.
	Muscle Damage	Minor	- See study	A slight decrease in biomarkers of muscle damage has been noted with CoQ10 supplementation.
	Pre-Eclampsia Risk	Minor	- See study	A reduction in risk has been noted, but not to an overly amazing degree
	Quality of Life	Minor	Moderate See all 3 studies	An increase in QOL has been noted in persons who either have heart ailments or are at risk for them, but this may not be a universal increase (perhaps dependent on reducing disease state symptoms)
	Rate of Perceived Exertion	Minor	- See study	A decrease in the rate of perceived exertion has been noted with CoQ10 supplementation
	Seminal Motility	Minor	Very High See all 3 studies	Requires more evidence to assess potency, but it does appear to reliably increase seminal motility
	Sperm Quality	Minor	Moderate See all 4 studies	There may be some beneficial influences on the sperm quality, but they have not been reliably reported
	Symptoms of Parkinson's Disease	Minor	- See study
	Testosterone	Minor	- See study	Not the largest increase, and was in infertile men; may not apply to fertile men.
	VO₂ Max	Minor	Very High See 2 studies	An increase in VO2 max of untrained persons has been noted following CoQ10 supplementation.
	Adiponectin	-	- See study	No detectable interaction of CoQ10 and adiponectin
	Anaerobic Running Capacity	-	- See study	No significant influence on anaerobic cardiovascular exercise has been detected with CoQ10 (although an anti-fatigue effect has been noted)
	Blood Glucose	-	Very High See 2 studies	Insufficient evidence to support changes in blood glucose with CoQ10 supplementation
	C-Reactive Protein	-	Very High See 2 studies	No significant influence on levels of C-reactive protein
	Exercise Capacity	-	- See study	No significant detectable effect on exercise capacity when preloaded
	Insulin	-	- See study	Insufficient evidence to support changes in insulin associated with CoQ10 supplementation.
	Oxygen Uptake	-	- See study	No detectable influence on oxygen uptake during exercise
	Total Cholesterol	-	Very High See 2 studies	No significant or consistent effects on total cholesterol levels noted with CoQ10
	Symptoms of Prader Willi Syndrome	Notable	- See study	Notable due to the aid to psychocognitive capabilities being comparable to the growth hormone active control (although not as effective in regards to physical development). Study in infants, not enough evidence in adults
	Cardiac Mass	Minor	- See study	A decrease in cardiac mass has been noted with CoQ10 supplementation
	Fertility	Minor	- See study	Insufficient evidence to support whether the increase in fertility is large or not, but preliminary evidence suggests that it exists.
	Left Ventricular Ejection Fraction	Minor	- See study	Has been noted to increase LVEF in persons with myocardial impairment
	UV Damage	Minor	- See study	A decrease in UV damage has been detected with supplemental CoQ10

Studies Excluded from Consideration

• Confounded with the inclusion of other nutrients^[1][2]

• Examining coenzyme Q10 for migraine relief

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