CoQ10: Ubiquinol vs ubiquinone, what the evidence shows

Ubiquinone and ubiquinol are the same molecule, coenzyme Q10, in two states.^[5] Ubiquinone is the oxidised form, and ubiquinol is the reduced form, which simply means it carries two extra electrons.^[5] Your body switches between the two all day. That is why about 95 percent of the CoQ10 in a healthy adult's blood is ubiquinol, whichever form went into the capsule.^{[31, 5]}

That switching is the molecule's job. Inside your mitochondria, the cell's power plants, CoQ10 passes electrons along the chain that produces ATP, the energy molecule cells run on.^[5] Ubiquinone picks up two electrons, and ubiquinol hands them on to the next step of the chain.^[5] Ubiquinol can also hand them to a free radical and neutralise it, so the reduced form works as an antioxidant that protects fatty cell membranes.^[5] Without CoQ10 the mitochondria cannot make most of the cell's ATP, so every cell makes its own.

Supplements took longer to reach the reduced form. Ubiquinol oxidises easily, so for decades supplements could only be made as ubiquinone.^[5] A label that just says "CoQ10" therefore still almost always means ubiquinone, whose drug name is ubidecarenone. The table sets the two forms side by side, from what they are to what they cost.

Prices: Shop-Apotheke, checked in October 2026; details in the buying section.

Since the body converts one form into the other, the label names the starting state, not what ends up in your blood^{[5, 31]} What differs between products is how much CoQ10 gets absorbed in the first place, and that depends heavily on how the capsule is made.^{[4, 5]} Absorption is also where ubiquinol's makers place their best-known selling point, the claim of "2 to 3x" better uptake.

The "2 to 3x more bioavailable" line for ubiquinol usually rests on five studies. Each was funded by, or written by staff of, the company whose ubiquinol it tested.^{[7, 8, 9, 23, 24]} Kaneka, the Japanese company that developed the first commercial ubiquinol ingredient, KanekaQH, is behind several of them.^{[48, 7, 8, 23]} Sponsor ties like these are common in supplement science, and the papers disclose them, so the useful question is how each study was designed.

The table lists the five studies with their design, who paid or wrote them, and what they found. All except Hosoe, which had no ubiquinone arm, report the sponsor's ubiquinol as superior.

The Langsjoen study shows why the design matters as much as the sponsor. Its participants knew which form they were taking, and everyone took ubiquinone first and ubiquinol second^[23] A blinded trial in random order avoids both problems, which is why that result carries less weight than its headline suggests.

Mei 2026, the newest of the five, shows how much the arithmetic matters. Its headline advantage comes from adjusting each person's result for the CoQ10 already in their blood before the dose.^[9] With that adjustment, the peak level was about 2.2x higher with the sponsor's ubiquinol, but without it the advantage shrank to about 1.5x.^[9] The trial was also too small to be reliable. By its own after-the-fact calculation, it had only a 10 to 34 percent chance of spotting a real difference, where 80 percent is the usual standard.^[9]

None of these papers is fraudulent, and each looks defensible on its own, but all five come from the maker of the product they tested.^{[7, 8, 9, 23, 24]} The other side has a stake too. The review that calls ubiquinol's superiority "mistaken" was written by two employees of Pharma Nord.^[5] The company mainly sells ubiquinone, though it also offers a ubiquinol product (as of October 2026). Its authors argue that the claim grew partly out of an unfair comparison: a 2007 Kaneka ubiquinol study set against a 1998 study of a poorly absorbed ubiquinone powder.^[5] A modern ubiquinone softgel is a different product from that powder, and with both camps selling something, the comparisons that neither of them designed carry the most weight.

Comparisons of ubiquinol and ubiquinone that the makers did not design give mixed results, and how a product is made matters more than the form.^{[4, 5, 32, 33, 34]} In one eight-week trial in 150 healthy adults, both forms raised blood CoQ10 at label dose.^[34] Ubiquinol's average rise was somewhat larger, but the difference was not significant, so chance cannot be ruled out.^[34] Even this trial has an industry tie, since its lead author sits on a supplement company's scientific advisory board.^[34]

Formulation explains why the form matters less than expected. An academic group in Seville tested seven commercial 100 mg products in 14 young adults.^[4] Absorption varied several-fold because the oil and the other ingredients mattered, and the two best performers were both softgels, one ubiquinone and one ubiquinol.^[4]

The test also included two Pharma Nord ubiquinone softgels that differed in a single manufacturing step.^{[4, 5]} Both held the same ubiquinone in the same soy oil, but one had gone through a patented heat process that breaks up the CoQ10 crystals.^[5] That one was absorbed about four times better.^[5] The ubiquinol in the test reached about twice the level of the weaker softgel but only about half that of the better one.^[5] Ubiquinol cannot be given that crystal treatment because it is less stable.^[5] From this, the Pharma Nord authors conclude that the idea of superior ubiquinol "would appear to be mistaken".^[5]

The way CoQ10 is absorbed points the same way. Swallowed ubiquinone is converted to ubiquinol on its way into the blood, so the reduced form ends up there either way.^[5]

Blood levels are only half the question, and a review from the University of Graz looked at health outcomes instead. After going through 28 study reports, it recommends ubiquinone rather than ubiquinol for people with heart failure.^[6] That comparison is indirect, because the five ubiquinol trials were small and short and could not show a difference in deaths.^[6] The review has a stake as well, since its lead author works part-time for Apomedica, whose Dr. Böhm brand sells a ubiquinone capsule.^[6] On blood levels and on outcomes alike, then, both forms can do the job: ubiquinol has no reliable lead, and the capsule it comes in matters more than the form inside.^{[4, 5, 34]}

Ubiquinol is a reasonable choice for three groups: people on statins, older adults, and people who absorb fat poorly. The case rests on how absorption works and on small blood-level studies, since we found no trial in these groups comparing the two forms on symptoms or outcomes.^{[13, 32, 33]} For everyone else, formulation and dose matter more than the form.^{[4, 5]}

Statin users are the group most often pointed to. Statins block an enzyme that sits upstream of both cholesterol and CoQ10 production, and a pooled analysis of placebo-controlled trials found that they lower blood CoQ10.^[10] How much that matters clinically is unclear.^[10] The hope is that the reduced form refills the body's stores faster, yet the one ubiquinol trial in people with confirmed statin muscle pain was negative.^[13] Taking 600 mg a day for eight weeks did not ease the pain.^[13] Slightly more people even reported pain on ubiquinol than on placebo, a borderline result.^[13] Because that trial had no ubiquinone arm, it says nothing about which form is better.^[13]

For older adults, the argument starts with age itself. An older study of human organs found that CoQ10 content peaked around age 20 in most organs and then fell steadily.^[20] Whether ubiquinol makes up for that better is unclear, because the two small comparisons in older people disagree. In 10 men over 55, two weeks of ubiquinol raised blood CoQ10 more than ubiquinone, in a study not funded by a supplement maker.^[32] In 21 adults aged 65 to 74, a single dose of ubiquinol gave a higher level, but the difference was not significant.^[33] Both studies measured blood levels only. The Pharma Nord review adds that the two large ubiquinone outcome trials ran in people with average ages of 63 and 78.^[5] In its authors' view, that shows older people absorb a well-made ubiquinone well enough to benefit.^[5]

Poor fat absorption is the third case. CoQ10 is absorbed with the help of bile, like other fats.^[5] Fat absorption suffers when bile, pancreatic enzymes or the gut lining do not work well, as in cystic fibrosis, inflammatory bowel disease, chronic pancreatitis or after weight-loss surgery. For these people the reduced form may be absorbed better, which is plausible, but we found no trial comparing the two forms in these groups.

In all three groups the choice is cheap to make, because some Kaneka ubiquinol softgels cost about the same as a good ubiquinone softgel (see the buying section).

CoQ10 shows its strongest benefit in heart failure, where one mid-sized trial found fewer major heart events, and it has modest support in adult migraine.^{[1, 14]} In male fertility it raises sperm counts, though pregnancy results are mixed.^[16] Statin muscle pain gives mixed results, blood pressure drops a little at most, and in Parkinson's disease it did not help.^{[39, 38, 17]} Inherited CoQ10 deficiency is the one clear treatment use.^{[42, 43]} So CoQ10 has a real place in a few specific conditions; almost all of this evidence comes from patients rather than from healthy people taking it for longevity.

Heart failure and heart deaths

Q-SYMBIO gave 420 people with moderate to severe heart failure 100 mg of ubiquinone three times a day for two years.^[1] After 16 weeks, symptoms, walking distance and NT-proBNP (a blood marker of heart strain) had not changed.^[1] Over two years, though, fewer people had a major heart event: 15 percent versus 26 percent on placebo.^[1] Deaths were also lower (10 vs 18 percent), but that was a secondary result, one the trial was not designed to test.^[1] Other studies point the same way. An older one-year trial reported fewer hospital stays for worsening heart failure.^[46] A review pooling mostly small trials found fewer deaths and hospital stays as well, and rated the evidence moderate in quality.^[53]

KiSel-10, the other trial often quoted, did not study heart failure. It gave 443 older Swedes living at home, aged 70 to 88, selenium plus 200 mg of CoQ10 a day for four years.^{[2, 3]} The authors call them healthy, though about three in four had high blood pressure and about one in five had heart disease or diabetes.^[3] Deaths from heart disease were lower and stayed lower 12 years later.^{[2, 3]} Because selenium was given too and the trial was small, the authors call the result hypothesis-generating, a lead for new trials rather than proof.^[3] Pharma Nord provided the trial capsules.^[3]

Even so, CoQ10 is not among the recommended treatments in the 2021 ESC heart-failure guideline and its 2023 update,^{[49, 50]} or in the 2022 AHA/ACC/HFSA guideline.^[51] The new ESC heart-failure guideline from August 2026 does not mention CoQ10 at all.^[52] Likely reasons for the caution are that Q-SYMBIO is one mid-sized trial and that KiSel-10 also gave selenium. If you have heart failure, CoQ10 is well worth raising with your cardiologist, who can fit it to your treatment, rather than adding it on your own.

Migraine

In a trial of 42 adults with migraine, about half of those on CoQ10 had their attacks at least halved, against one in seven on placebo.^[14] They took 100 mg three times a day for three months.^[14] A later review pooling six studies confirmed fewer and shorter attacks, though not milder ones.^[15] A US neurology guideline once rated CoQ10 "possibly effective".^[27] That rating is no longer current, because the AAN retired the guideline in 2015 over safety concerns with butterbur, another treatment it recommended.^[27] In children and teenagers a trial found no benefit,^[29] so for adults with migraine, CoQ10 offers modest support for fewer and shorter attacks.

Male fertility

In men with fertility problems, a review pooling three trials found that CoQ10 raised sperm concentration and sperm movement (motility).^[16] Pregnancy rates did not rise, though, and none of those trials measured live births.^[16] Later reviews disagree on pregnancy: one found no clear difference and called the trials poor,^[37] while another reported more pregnancies, but from small trials.^[36] CoQ10 can improve sperm quality, then; whether that turns into more babies is still open, because live-birth data are missing.

Statin muscle pain

For muscle pain on statins, the results are mixed. One review found no clear benefit,^[11] and an update with more trials found less muscle pain, weakness, cramps and tiredness.^[12] A recent review of seven small trials found a small reduction in muscle pain and asked for more research.^[39] The one trial in confirmed statin muscle pain, which used ubiquinol, was negative.^[13] CoQ10 is the most popular remedy for statin muscle pain among doctors and patients.^[13] Yet the European Atherosclerosis Society does not recommend it to treat or prevent these symptoms.^[40]

Do not stop or lower your statin on your own because of ordinary muscle aches. Muscle symptoms are a main reason people stop statins, which raises heart risk, and your doctor can check the cause and try another statin or dose.^[40] Severe or unexplained muscle pain or weakness, especially with dark urine, is different: it can signal rare serious muscle damage and needs a doctor straight away.^[40]

Parkinson's disease and blood pressure

In early Parkinson's disease, the QE3 trial gave 600 patients 1,200 or 2,400 mg a day with vitamin E, or a placebo.^[17] It was stopped early because it showed no benefit, so the slower decline hinted at by a smaller earlier trial did not hold up.^{[55, 17]}

Blood pressure is measured in mmHg, the unit any home monitor shows, and claims for CoQ10 rest mostly on an older review of 12 mostly small trials.^[28] It reported drops of up to 17 mmHg in systolic pressure (the upper number) and 10 mmHg in diastolic pressure (the lower one).^[28] Those numbers compare values before and after treatment rather than against a placebo, and most of the trials were open-label, so participants knew what they took.^[28] Later reviews found much less. A Cochrane review that kept only blinded randomised trials found moderate-quality evidence of no clinically significant effect.^[18] A recent review of 45 trials found a small drop of about 3 to 4 mmHg in systolic pressure and no effect on diastolic pressure.^[38] A small effect on the upper number is therefore the most the current evidence supports.

Inherited CoQ10 deficiency and other mitochondrial diseases

In inherited defects of CoQ10 production (primary CoQ10 deficiency), high-dose CoQ10 replaces what the body cannot make and is standard specialist treatment. For other mitochondrial diseases such as MELAS or Leigh syndrome, a US specialist society advises offering it.^[42] A Cochrane review, however, found no clear trial evidence that any treatment helps.^[41] Specialist dosing tables give 10 to 30 mg per kg of body weight a day for ubiquinone in children and 300 to 2,400 mg a day in adults.^[43] Doses of ubiquinol are lower.^[43] This is treatment under a specialist, not self-supplementation.

Healthy people

For healthy people, CoQ10 is a field where the biology is solid and the trials are still catching up. In 41 young adults, two weeks of 200 mg a day raised blood CoQ10, but exercise performance did not clearly improve and time to exhaustion only tended to.^[30] EFSA rejected a claim that CoQ10 supports energy metabolism in 2010.^[19] The everyday levers that form the foundation of healthy ageing, with better evidence behind them, are in the guide on how to slow aging. For a healthy person, then, CoQ10 is a reasonable experiment that rests on its biology more than on trial results so far.

The heart-failure trial Q-SYMBIO and the adult migraine trial both used 300 mg a day, taken as 100 mg three times daily.^{[1, 14]} Those are trial doses for patients under medical care, not a supplement dose. The EU itself sets no legal maximum for CoQ10.^[26] In Germany, a 2014 general ruling by the federal food-safety office BVL permits supplements with up to 100 mg a day.^[26] The condition is a label warning against use in pregnancy, breastfeeding and under 18.^[26] Switzerland sets a maximum of 200 mg a day (as of October 2026),^[47] and higher doses belong with a doctor. For a healthy person, CoQ10 is an optional extra you can try rather than a gap to fill: the body makes its own, and Germany's risk agency BfR sees no need for healthy people to supplement at all.^[26]

To get the most out of it, take it with food. CoQ10 is absorbed with the help of bile, like other fats,^[5] so a meal that contains some fat is the sensible time. An oil softgel is a sensible format too, though it does not guarantee good absorption.^{[4, 5]} The gut can absorb only so much at once: in one study, two doses of 100 mg raised blood levels more than one dose of 200 mg.^[5] So if you take more than 100 mg a day, split it across meals.

Once in the blood, CoQ10 stays a long time. Its half-life, the time it takes for the blood level to fall by half, is about 33 hours.^[5] That slow turnover is why blood levels take one to two weeks to level off after you start or change a dose.^[5] A blood test right after a dose change therefore tells you little. Two weeks at a stable dose is the earliest point at which a test makes sense.

Interactions and who should be careful

• Warfarin and phenprocoumon. CoQ10 is chemically similar to vitamin K, and an old case-report letter suggested it can weaken warfarin.^[21] A later randomised trial in 24 patients found that 100 mg a day did not change the warfarin dose needed.^{[22, 35]} BfR advises asking a doctor before taking more than 100 mg a day with a coumarin-type blood thinner such as warfarin or phenprocoumon.^[26] If you take one of these, ask your doctor to check your INR (the standard clotting test) after you start or stop CoQ10, at a time your doctor sets.
• Apixaban and other newer blood thinners. The INR does not measure the effect of apixaban or similar newer blood thinners,^[54] and we found no CoQ10 study with them, so tell your prescriber before starting.
• Blood-pressure drugs. A small additional drop of a few mmHg is possible, and the interaction has not been studied properly.^{[38, 26]} BfR advises a doctor's okay above 100 mg a day if you take blood-pressure drugs.^[26]
• Cancer treatment. If you are in cancer treatment, ask your oncology team before starting.
• Pregnancy, breastfeeding and under 18. BfR advises against relevant doses in pregnancy, breastfeeding and under 18 unless a doctor clears it.^[26] Supplements sold in Germany under the BVL ruling must carry a warning that pregnant and breastfeeding women and under-18s should not take them.^[26]

Side effects

Up to 300 mg a day, studies report occasional stomach and gut complaints (nausea, heartburn, stomach ache, diarrhoea) and isolated skin rashes.^[26] According to BfR, whether side effects become more common above 300 mg a day has not been researched.^[26] Short trials in healthy volunteers gave up to 900 mg a day for four weeks without side effects rising with the dose.^[56] Trials in disease used up to 2,400 mg a day,^[17] but data on long-term use in healthy people remain thin.^[26] Neither form has been shown to be safer. The one trial that gave both reported rare side effects in all groups, and BfR sees data gaps for both forms.^{[34, 26]}

In Germany, Austria and Switzerland CoQ10 is sold as a food supplement, not as a medicine.^[26] In Switzerland it falls under food law rather than under the medicines agency Swissmedic, and a supplement may supply up to 200 mg a day.^[47] Statutory insurers (GKV, ÖGK, Swiss basic insurance) do not pay for supplements. For an inherited CoQ10 deficiency a specialist can prescribe it, for example as a pharmacy-made preparation; ask the treating centre about cost coverage.

Pharmacies sell it locally and online, for example Shop-Apotheke, DocMorris, easyApotheke and Apotal. You also find it at the drugstores dm, Rossmann and Müller, on Amazon and directly from brands such as Sunday Natural, Sanct Bernhard and Pharma Nord. In Switzerland, Burgerstein, Pure Encapsulations and Pharma Nord are among the brands sold. The drugstores' own brands (dm Mivolis, Rossmann Altapharma) carry CoQ10 mostly as one ingredient in combination products, not as a 100 mg single product.

The table compares common products. Where a price is given, we checked it at Shop-Apotheke in October 2026 ("from" prices, pack sizes vary). The other prices change too often to print, so compare them per 100 mg yourself.

Those prices show that the form itself is not what makes a product expensive. Kaneka ubiquinol softgels from Sanct Bernhard and Doppelherz cost about €0.53 to €0.71 per 100 mg, roughly the same as Pharma Nord's ubiquinone softgel at €0.69. Powder-capsule ubiquinone is far cheaper at €0.16 to €0.27. At 100 mg a day, the cheapest product in the table costs about €5 a month and the Pharma Nord softgel about €21. Pure Encapsulations' 50 mg ubiquinol comes to about €59. The spread reflects form, carrier, licensing and brand, and no study shows that a higher price brings proportionally more CoQ10 into your blood.

The product the two outcome trials used is Pharma Nord's Bio-Qinon Gold, sold as Myoqinon outside DACH, the ubiquinone softgel given in KiSel-10.^[3] and Q-SYMBIO^[1] The same company employs the authors of the main review against the ubiquinol claim,^[5] so keep the vendor in mind when you read its arguments.

If you prefer ubiquinol, a KanekaQH or Kaneka Ubiquinol seal tells you that the ingredient comes from Kaneka, the company that developed it.^[48] Ubiquinol without a Kaneka mention comes from other suppliers and is often cheaper. With any brand, a certificate of analysis tells you what is in the batch, and these label checks cover most of the rest:

1. The form is declared (Ubiquinon, Ubichinon or Ubiquinol), not a vague "reduced CoQ10".
2. The dose is given per capsule, not per "daily portion" spread over two capsules.
3. The carrier is in the ingredient list: an oil (MCT, soybean, olive), sunflower lecithin or vitamin E points to an oil softgel, while rice flour or microcrystalline cellulose points to a dry capsule. An oil softgel is a sensible format but no guarantee of good absorption.^{[4, 5]}
4. The manufacturer is named, plus the Kaneka seal for ubiquinol.
5. A certificate of analysis (the lab report on what is in the batch) is available on request.

EU labels carry no CoQ10 health claims because EFSA, the EU food-safety authority, found none of six claim types backed by enough evidence of cause and effect.^[19] It assessed them in 2010, and since then we found no EFSA opinion that backs a CoQ10 claim (as of October 2026).

The six rejected claims, assessed under Article 13(1) of Regulation (EC) No 1924/2006, were these^[19]:

1. Contribution to normal energy-yielding metabolism
2. Maintenance of normal blood pressure
3. Protection of DNA, proteins and lipids from oxidative damage
4. Contribution to normal cognitive function
5. Maintenance of normal blood cholesterol concentrations
6. Increase in endurance capacity or endurance performance

In practice, that means a label in the EU may not attribute any health benefit to CoQ10 itself. Combination products may carry authorised claims for other ingredients they contain, such as certain vitamins, under those ingredients' conditions. A heart or energy claim tied to CoQ10 itself is still not compliant.

The one exception lies outside these food rules: in inherited CoQ10 deficiency, a specialist prescribes CoQ10 for a named patient, for example as a pharmacy-made preparation. For everyone else, the trials in this guide are scientific evidence, not permitted label claims, and a positive study does not change what a seller may print.

CoQ10 does its clearest good in heart failure and adult migraine, and for a healthy adult it is an optional experiment, so the first question is what you want from it, and only then which form to pick. The body makes its own, as the Mitochondria guide explains, and Germany's risk agency BfR sees no need for healthy people to supplement.^[26] The trial benefits came at 300 mg a day in patients, doses to set up with a doctor.^{[1, 14]} The Longevity Supplements guide covers the alternatives.

Once you decide to take it, choosing is easier than the marketing suggests: the form matters less than how the product is made and how you take it. Comparisons outside the ubiquinol makers' own studies ranged from a small advantage for ubiquinol to no significant difference, while formulation changed absorption several-fold.^{[32, 33, 34, 4, 5]} Ubiquinol remains a reasonable pick if you take a statin, are older or absorb fat poorly. Still, no trial has compared the two forms on clinical outcomes in these groups, and no ubiquinol trial has shown fewer deaths so far.^[6] Because some Kaneka ubiquinol softgels cost about the same per 100 mg as a good ubiquinone softgel, choosing it need not cost you more.

If you are a healthy adult without a statin or a fat-absorption problem and want to try it, 100 mg a day is a reasonable start.^[26] That is the amount the German BVL ruling permits for supplements.^[26] Take it as an oil softgel with a meal that contains some fat, whichever form is inside, and if you want to judge an effect, give it three months at a steady dose.