Coenzyme Q10: Everything You Need to Know!

Date: September 3, 2023 Categories: Knowledge Views: 29

Long read alert, manual table of contents

Distribution of Coenzyme Q10 in the Human Body
Benefits of Coenzyme Q10
Key term: Bioavailability
Is reduced Coenzyme Q10 better than oxidized Coenzyme Q10?
Is water-soluble Coenzyme Q10 better than fat-soluble Coenzyme Q10?
What is a safe daily intake?
Other considerations
Common technologies and products

In 1957, American biochemist Dr. Frederick Crane extracted a quinone substance from bovine heart mitochondria, marking the first discovery of Coenzyme Q10 in humans. Dr. Karl Folkers received the highest honor from the American Chemical Society—the Priestly Medal—in 1986 for being the first to determine the structure of Coenzyme Q10. Dr. Crane took Coenzyme Q10 consistently for 40 years, passing away at the age of 91.

In 1961, Dr. Peter D. Mitchell from the University of Edinburgh discovered how Coenzyme Q10 generates energy at the cellular level, a groundbreaking finding that earned him the Nobel Prize in Chemistry (Physiology) in 1978.

Due to its significance, the FDA has approved Coenzyme Q10 for applications related to mitochondrial diseases. In China, Coenzyme Q10 is widely used as an adjunct therapy for heart protection, hypertension, and other conditions.

Many people turn to Coenzyme Q10 supplements when facing various health issues. After reading this article, you should be able to make an informed decision about the right form of Coenzyme Q10 for yourself:

Distribution of Coenzyme Q10 in the Human Body

Coenzyme Q10 is widely present in cell membranes, especially in mitochondrial membranes, primarily found in the heart, lungs, liver, kidneys, spleen, pancreas, and adrenal glands. The total body content of Coenzyme Q10 is only 500-1500 mg, yet it plays a crucial role.

Coenzyme Q10 levels are highest in the heart, kidneys, liver, and muscles, with about 95% existing as ubiquinol (the reduced form), except in the brain and lungs. This may be due to higher oxidative stress in those tissues, which converts ubiquinol to its oxidized form, ubiquinone.

As we age, the levels of Coenzyme Q10 in the body gradually decline. Using 20 years as a baseline, by the age of 80, the natural decline of Coenzyme Q10 in various organs is as follows:

Liver: 83.0%
Kidneys: 65.3%
Lungs: 51.7%
Heart: 42.9%

Thus, it's generally accepted that the heart is the organ most in need of Coenzyme Q10 supplementation, and many age-related heart issues may stem from Coenzyme Q10 deficiency.

Interestingly, recent surveys in Australia indicate that levels of Coenzyme Q10 in the blood actually increase with age (in individuals not taking any supplements), possibly due to the depletion of skeletal muscle cells leading to the release of Coenzyme Q10 into the bloodstream as cells die.

Benefits of Coenzyme Q10

The primary biochemical role of Coenzyme Q10 is as a cofactor in the electron transport chain, participating in a series of redox reactions involved in ATP synthesis. Since most cellular functions depend on a sufficient supply of ATP, Coenzyme Q10 is believed to be vital for all tissues and organs.

ATP: An unstable high-energy compound made up of one molecule of adenine, one molecule of ribose, and three phosphate groups. Also known as adenosine triphosphate. In cells, it interconverts with ADP, storing and releasing energy to ensure energy supply for various life activities.

Additionally, Coenzyme Q10 is one of the most important lipid-soluble antioxidants, preventing free radical production and changes to proteins, lipids, and DNA.

Given these reasons, it is widely accepted that Coenzyme Q10 is linked to improved health and anti-aging effects. Theoretically, as long as the supplemented Coenzyme Q10 reaches key areas at the cellular level, these functions can be achieved. However, in reality, ingesting it does not guarantee absorption, and absorption does not equal utilization. We will address the concept of bioavailability in the next chapter.

Here, we will summarize existing human or animal studies and perspectives from reputable institutions to explain the credibility of the benefits of oral Coenzyme Q10.

First, in the classification of safety and efficacy for drug ingredients in the U.S., this classification also extends to dietary supplements. Here’s how efficacy is categorized:

EFFECTIVE: Proven effective (through FDA review, backed by substantial clinical trials).
LIKELY EFFECTIVE: Likely effective (supported by a large amount of clinical evidence).
POSSIBLY EFFECTIVE: Possibly effective (based on one or more clinical trials).
POSSIBLY INEFFECTIVE: Possibly ineffective (one or more trials show ineffectiveness).
LIKELY INEFFECTIVE: Likely ineffective (proven ineffective by substantial clinical trials).
INEFFECTIVE: Ineffective (strong clinical evidence proves ineffectiveness).
INSUFFICIENT EVIDENCE: Not enough evidence to support.

There are about seven reliability levels, with three classified as effective.

Furthermore, the FDA has not yet approved Coenzyme Q10 for the treatment of any specific diseases, but it is widely available as an over-the-counter supplement.

This creates a paradox: the highest level of EFFECTIVE (and SAFE) requires FDA approval, yet the FDA does not regulate dietary supplements. Therefore, the highest certification level for supplements (like Coenzyme Q10) is at most LIKELY EFFECTIVE.

Note: In the U.S., dietary supplements are classified as food products. Manufacturers only need to submit a statement declaring that their product has no known side effects to sell it. The FDA does not review products before they hit the market but can intervene if a product is deemed unsafe or if its health benefits are falsely or misleadingly advertised. Many domestic merchants claiming “FDA-certified supplements” are misleading.

However, just because something is not classified as EFFECTIVE does not mean it is INEFFECTIVE. There are still two efficacy levels (LIKELY EFFECTIVE and POSSIBLY EFFECTIVE) that suggest it is not a therapeutic drug but may not necessarily be ineffective. Let’s look at the various claims of Coenzyme Q10 available on the market and their credibility levels:

A: Is it effective for heart health?

Answer: LIKELY EFFECTIVE.

Since Coenzyme Q10 was initially extracted from bovine hearts, and because the heart has the highest concentration of Coenzyme Q10, there is a significant amount of related research.

Supporting Evidence:

Mayo Clinic states that “CoQ10 might help prevent or treat certain heart conditions.”
Numerous studies highlight Coenzyme Q10's protective effects on the heart, such as the one published in "Clinical Evidence for Q10 Coenzyme Supplementation in Heart Failure," which presents extensive evidence of its heart-improving effects.
In clinical trials recorded in the U.S., there have been 13 studies on Coenzyme Q10 related to heart health, with 10 completed, all showing positive results.

B: Is it useful for pregnancy preparation?

Answer: LIKELY EFFECTIVE.

Supporting Evidence:

The American Pregnancy Association suggests that improving a woman's resistance might justify supplementing with Coenzyme Q10.
Several studies indicate that Coenzyme Q10 supplementation can enhance male sperm quality, notably one published in Nature Reviews Urology, which involved 354 men with idiopathic oligozoospermia receiving 300 mg of treatment daily for 12 months. Post-treatment, sperm concentration, total sperm count, and percentage of normal sperm showed significant increases, with a total pregnancy rate of 34.1% compared to just 6.4% in the untreated group.
There have been 6 trials regarding Coenzyme Q10 during pregnancy, 5 of which have been completed, all showing it to be effective compared to a placebo.

Additionally, both men and women can benefit from supplementing with Coenzyme Q10 during the conception phase.

Likely effective for the following conditions:

(1) Coenzyme Q-10 deficiency

Taking coenzyme Q-10 orally appears to improve symptoms of coenzyme Q-10 deficiency, a very rare condition. Symptoms include weakness, fatigue, and seizures.

(2) Genetic or acquired diseases that restrict cellular energy production (mitochondrial diseases)

Oral coenzyme Q-10 seems to alleviate symptoms of mitochondrial diseases; however, improvement is gradual, and some individuals may need to take coenzyme Q-10 for six months to see maximum benefits.

Possibly effective for the following conditions:

(1) Age-related vision loss (age-related macular degeneration)

Certain products containing coenzyme Q-10, acetyl-L-carnitine, and omega-3 fatty acids (Phototrop) seem to improve vision in patients with age-related vision loss.

(2) Congestive heart failure (CHF)

Some studies suggest that low coenzyme Q-10 levels may be linked to heart failure. While most evidence indicates that taking coenzyme Q-10 alone does not help treat heart failure, there is some evidence that combining it with other heart failure medications may be beneficial.

(3) Nerve damage caused by diabetes (diabetic neuropathy)

Research indicates that coenzyme Q-10 supplementation may improve nerve damage and pain in individuals with diabetes-related nerve injury.

(4) HIV/AIDS

Oral coenzyme Q-10 appears to enhance immune function in HIV/AIDS patients.

(5) A genetic neurological disorder known as Huntington's disease

Ubiquinol, a modified form of coenzyme Q-10, has received orphan drug status from the FDA, providing manufacturers some economic incentive to study its effectiveness for this very rare condition (affecting fewer than 200,000 people), as pharmaceutical companies might not invest in developing treatments for it.

However, taking 600 mg or less of coenzyme Q-10 daily does not seem to effectively slow the progression of Huntington's disease.

(6) High blood pressure

Most studies indicate that taking coenzyme Q-10 alone or in combination with other antihypertensive medications may help reduce blood pressure. However, a small study suggests that oral coenzyme Q-10 may not lower blood pressure in individuals with metabolic syndrome.

(7) Vascular complications from heart bypass surgery

During heart or vascular surgery, reduced blood supply can deprive tissues of oxygen. When blood flow returns, the tissues may be damaged. There is evidence that taking coenzyme Q-10 a week before heart bypass or vascular surgery may help reduce tissue damage, although not all studies agree on this finding.

(8) Specific types of high blood pressure

Taking coenzyme Q-10 daily seems to lower systolic blood pressure (the top number) in some individuals with high systolic but normal diastolic blood pressure (the bottom number).

(9) Migraines

Oral coenzyme Q-10 appears to help prevent migraines. Research suggests it can reduce the frequency of headaches in adults by about 30% and the number of days with headache-related nausea by about 45%. It may also decrease migraine frequency in children with low coenzyme Q-10 levels. Significant benefits may take up to three months. However, once a migraine occurs, coenzyme Q-10 does not seem to effectively treat it.

(10) A genetic muscle disease known as muscular dystrophy

Oral coenzyme Q-10 seems to improve physical function in certain muscular dystrophy patients.

(11) Heart attacks

Starting coenzyme Q-10 within 72 hours after a heart attack and continuing for a year appears to lower the risk of heart-related events, including another heart attack.

(12) Parkinson's disease

Some studies suggest that coenzyme Q-10 supplementation may slow deterioration in early-stage Parkinson's patients, but it does not seem to improve symptoms in those with mid-stage Parkinson's.

(13) Peyronie's disease (painful erections in men)

Research indicates that taking coenzyme Q-10 can improve erectile function in men experiencing erection pain.

Likely ineffective for the following conditions:

(1) Alzheimer's disease

Taking coenzyme Q-10 does not appear to improve cognitive function in Alzheimer's patients.

(2) A neurodegenerative disease known as ALS or Lou Gehrig's disease

Research shows that taking coenzyme Q-10 does not slow the progression of ALS.

(3) Cocaine dependence

The combination of coenzyme Q-10 and L-carnitine does not reduce cocaine use.

(4) High cholesterol

Some studies indicate that taking coenzyme Q-10 does not lower total cholesterol, triglycerides, or low-density lipoprotein (LDL or "bad" cholesterol) or increase high-density lipoprotein (HDL or "good" cholesterol). Other studies show that taking coenzyme Q-10 alone or with carnitine does not improve cholesterol levels. However, one study involving a population that cannot take statins indicated that a combination of coenzyme Q-10, berberine, polycosanol, red yeast rice, folic acid, and astaxanthin may reduce cholesterol levels.

(5) Symptoms affecting polio survivors (post-polio syndrome)

Research indicates that taking coenzyme Q-10 does not improve muscle strength or function in patients with post-polio syndrome.

Possibly ineffective for:

Exercise performance. Oral coenzyme Q-10 does not improve exercise performance in athletes or non-athletes.

Insufficient evidence to assess effectiveness for the following conditions:

(1) Chest pain (angina).

Some early studies suggest that oral coenzyme Q-10 may improve exercise tolerance in angina patients.

(2) Asthma.

Some early studies suggest that combining coenzyme Q-10 with vitamin E (alpha-tocopherol) and vitamin C, in addition to standard asthma treatments, may reduce the amount of medication needed for individuals with mild to moderate asthma.

(3) Breast cancer.

Some studies involving Chinese women suggest that low coenzyme Q-10 levels in the blood are associated with an increased risk of breast cancer. Preliminary evidence indicates that taking coenzyme Q-10 alongside surgery, standard treatment, and other antioxidants and omega-3 and omega-6 fatty acids may help in advanced breast cancer.

(4) Cancer.

Research shows that low coenzyme Q-10 levels are associated with an increased risk of skin cancer. Additionally, early studies suggest that taking coenzyme Q-10 with other antioxidants may extend survival time for patients with advanced cancer by 40%.

(5) Cardiotoxicity from chemotherapy drugs.

Some studies indicate that taking coenzyme Q-10 may protect the hearts of children and adults receiving anthracycline chemotherapy drugs. However, other research suggests that intravenous coenzyme Q-10 (via IV) does not provide this benefit.

(6) A lung disease called chronic obstructive pulmonary disease (COPD).

Early studies suggest that taking coenzyme Q-10 may improve lung function and exercise tolerance in COPD patients.

(7) Cyclic vomiting syndrome.

Some early studies indicate that taking coenzyme Q-10 may be as effective as prescription medications used to treat cyclic vomiting syndrome.

(8) Diabetes.

Research on the effectiveness of coenzyme Q-10 for diabetes has yielded conflicting results. Some studies suggest that taking coenzyme Q-10 may lower blood sugar levels, while others find no benefit.

(9) Heart weakening and enlargement (dilated cardiomyopathy).

Early evidence indicates that taking coenzyme Q-10 may improve heart function in children with dilated cardiomyopathy.

(10) Dry mouth.

Early studies suggest that taking coenzyme Q-10 (ubiquinone) may improve dry mouth.

(11) Eye surgery.

Research shows that using eye drops containing coenzyme Q-10 and vitamin E can speed up nerve regeneration after cataract surgery.

(12) Fibromyalgia.

Some early studies suggest that taking coenzyme Q-10 and ginkgo may enhance well-being and overall health while reducing pain in fibromyalgia patients.

(13) Ataxia caused by brain injury (cerebellar ataxia).

Early research indicates that coenzyme Q-10 may improve muscle coordination and movement in cerebellar ataxia patients.

(14) A rare genetic disease causing nerve damage (Friedreich's ataxia).

Early studies suggest that taking vitamin E with coenzyme Q-10 may improve coordination, posture, and movement in patients with Friedreich's ataxia.

(15) Hearing loss.

Research shows that oral specific coenzyme Q-10 products (Q-TER) can improve hearing in patients with age-related hearing loss. However, combining coenzyme Q-10 with traditional steroid treatments does not appear to enhance hearing more than using steroids alone.

(16) Hepatitis C.

Research indicates that taking coenzyme Q-10 does not improve liver function in patients with hepatitis C who do not respond to standard treatments.

(17) A heart condition called hypertrophic cardiomyopathy.

Oral coenzyme Q-10 seems to reduce heart wall thickness in patients with hypertrophic cardiomyopathy and alleviate symptoms of breathlessness and fatigue.

(18) A rare genetic disorder known as Prader-Willi syndrome.

Early studies suggest that administering coenzyme Q-10 may improve development in children with Prader-Willi syndrome. However, it is unclear whether these improvements are due to coenzyme Q-10 or are age-related.

(19) Male infertility.

Some early evidence indicates that coenzyme Q-10 treatment may improve sperm motility and density in men with certain types of infertility. However, other studies show no beneficial effect on sperm motility.

(20) Genetic diabetes and deafness.

Some early evidence suggests that oral coenzyme Q-10 may slow the progression of a rare maternal hereditary diabetes.

(21) Gum disease.

Applying coenzyme Q-10 to the gums is ineffective for treating gum disease. However, there is some early evidence that taking coenzyme Q-10 orally may help treat gum disease.

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6. Does Coenzyme Q10 have side effects?

Most adults can safely take Coenzyme Q10 (CoQ10) orally at doses up to 3,000 mg daily for up to 8 months; 1,200 mg daily for up to 16 months; and 600 mg daily for up to 30 months, with no significant side effects reported.

Reported mild side effects include: stomach discomfort, allergic rash, loss of appetite, nausea, heartburn, vomiting, insomnia, fatigue, dizziness, light sensitivity, irritability, and diarrhea (especially at a daily dose of 200 mg).

7. Six contraindications for Coenzyme Q10 use

It is safe to start taking Coenzyme Q10 during pregnancy after about 20 weeks; however, safety during breastfeeding is still unknown, so it is advised not to use it.
Do not combine with chemotherapy drugs: alkylating agents, as Coenzyme Q10 may reduce the effectiveness of these medications. Related drugs include busulfan, carboplatin, cisplatin, cyclophosphamide, dacarbazine, and thiotepa.
Coenzyme Q10 may lower blood pressure, so those with low blood pressure or on antihypertensive medications should use it with caution. Related medications include captopril, enalapril, losartan, valsartan, diltiazem, amlodipine, hydrochlorothiazide, and furosemide.
Stop using it two weeks before any scheduled surgery, as Coenzyme Q10 may affect blood pressure control during and after surgery.
Do not combine with the anticoagulant Warfarin, as Coenzyme Q10 can promote blood clotting and may reduce the drug’s effectiveness. If both are needed, regular blood tests to monitor clotting time are essential, especially in the first two weeks.
Taking it before bed may cause insomnia, so it’s best to take it in the morning or afternoon.

8. How should Coenzyme Q10 be taken? What’s the dosage?

The standard dosage of CoQ10 ranges from 90 mg to 200 mg daily, depending on the individual and the condition being treated, with some studies using even higher doses.

Since CoQ10 is a fat-soluble compound, its absorption is slow and limited on an empty stomach. It’s recommended to take it with meals to enhance absorption.

Research shows that taking it with fatty foods can increase intestinal absorption by three times.

9. What forms does Coenzyme Q10 come in?

In the body, CoQ10 exists in two forms: the reduced form, ubiquinol, and the oxidized form, ubiquinone, with ubiquinol making up 90% of CoQ10 in the bloodstream.

Both forms help increase circulating levels of Coenzyme Q10.

A study comparing the two forms found that the reduced form, ubiquinol, increased plasma concentration by 4.77 times after four weeks, compared to 2.77 times for the oxidized form, indicating that ubiquinol has a significantly higher bioavailability (about 1.72 times higher, although related supplements are generally more expensive).

If the content is too long and you want to know which brand of Coenzyme Q10 is good, here’s a quick guide.

10. High-quality Coenzyme Q10 supplements in the U.S.

Labdoor evaluated 25 brands of Coenzyme Q10 supplements, and here are the top ten rankings.

Evaluation Criteria:

Label Accuracy: Testing if the actual content matches the label.
Product Purity: Testing for six heavy metals (cadmium, lead, arsenic, bismuth, antimony, and silver), and thankfully, all products passed (less than 2 PPM).
Nutritional Value: Testing nutrients and calories; Coenzyme Q10 is not a common nutrient we consume and contains almost no calories. Some products may contain sugar as an excipient, providing a small amount of calories.
Ingredient Safety: Testing if the content exceeds the maximum tolerable level. Currently, there’s no established maximum tolerable level for Coenzyme Q10, and even a daily intake of 1,200 mg shows no significant side effects.
Projected Efficacy: Testing if the content meets effective dosing. For heart failure and hypertension patients, the recommended supplement amount is at least 100-200 mg daily.

Ranked Brands:

Bulk Supplements - 196.7 mg
Garden Of Life - 196.1 mg
Solgar Vegetarian - 212.7 mg
Kirkland Signature - 302.4 mg
Nature Made - 197.2 mg
Nature’s Bounty - 205.9 mg
NutriONN - 192.1 mg
Viva Labs - 104.5 mg
Source Naturals - 108.3 mg
Nutrigold - 98.1 mg

The scores for these ten Coenzyme Q10 supplements are actually very close and comparable.

Most products have a dosage of 200 mg per serving, with only slight differences in actual content.

For health purposes, this is sufficient.

Costco’s Kirkland Signature brand has a higher dose at 300 mg per serving.

Note that the top-ranked Bulk Supplements Pure Coenzyme Q10 comes in powdered form, requiring you to measure out 200 mg and dissolve it in a drink or food. Other products are usually in capsule form, with Nature Made being the most commonly found in U.S. supermarkets.

11. Best Value Coenzyme Q10 Supplements in the U.S.

Ranked Brands and CoQ10 Content:

Viva Labs - 104.5 mg
Doctor’s Best - 103.1 mg
Puritan’s Pride - 100.2 mg
Nature’s Bounty - 205.9 mg
Kirkland Signature - 302.4 mg
Nutrigold - 98.1 mg
Bulk Supplements - 196.7 mg
NOW Foods - 89.5 mg
Source Naturals - 108.3 mg
GNC - 102 mg

Considering price, several products with lower doses of 100 mg per serving rank high. For most people without heart conditions, this dosage is sufficient for daily health.

Since Coenzyme Q10 is fat-soluble, it’s best taken with meals.

12. Popular Coenzyme Q10 Brands and Products in China

Ranked Brands and CoQ10 Content:

Puritan's Pride - 200 mg per capsule
Swisse - 150 mg per capsule
Schiff MegaRed - 200 mg per capsule
By-Health - 29.8 mg per capsule
Blackmores - 150 mg per capsule
GNC - 200 mg per capsule
Nature Made - 200 mg per capsule
NovaSOL - 200 mg per capsule
Doctor's Best - 200 mg per capsule
Doppelherz - 50 mg per capsule

Important Correction: A user pointed out that the Coenzyme Q10 content for By-Health was incorrectly labeled. I consulted By-Health’s customer service, and it was indeed my mistake. The correct information is that each capsule contains 29.8 mg of Coenzyme Q10 and 16.08 mg of Vitamin E; the 400 mg refers to the total weight of each capsule, not the Coenzyme Q10 content.

JD Purchase Links:

Puritan’s Pride offers six CoQ10 specifications on JD:

100 mg for heart health after staying up late
Two-bottle pack of 100 mg each
120 mg for enhanced heart support
200 mg for pre-pregnancy heart health
400 mg for maximum heart support
100 mg of ubiquinol

Choose based on your personal needs.

13. Additional Notes on Heart Specialist Coenzyme Q10

Some friends mentioned the Heart Specialist CoQ10, noting that many have already introduced this brand on platforms like Zhihu. I didn’t want to repeat what’s been said, but since there’s a request, here’s some information.

Heart Specialist is an American brand selling the reduced form of CoQ10 in China (specifically on JD), with 30 capsules per bottle, which is the Ubiquinol type.

Its key feature is the industry-leading MicroActive technology, allowing for rapid absorption in 6 hours and sustained absorption for 24 hours, achieving 40% more absorption than other reduced form CoQ10 products, promoting cell health and cardiovascular support, and potentially doubling CoQ10 levels in three weeks.

It also uses Water Dispersible technology to enhance intestinal absorption.

For those curious about MicroActive technology, it addresses the common absorption issue of fat-soluble CoQ10. Technologies aimed at enhancing Q10 absorption include emulsification (with tocopherol), additives (like BioPerine, D-Limonene), liposome technology (Mega-Liposomal), NovaSOL technology, and MicroActive technology.

Top-quality CoQ10 products now commonly use MicroActive® water-soluble CoQ10 technology, which boosts peak absorption by 800% compared to traditional products.

MicroActive® Patent Original Text

The curve above illustrates the human absorption curve for MicroActive® CoQ10.

Below is the absorption curve for traditional crystalline CoQ10.

MicroActive® shows approximately four times the absorption efficiency of traditional crystalline CoQ10.