coq10

Coenzyme Q10 (CoQ10) is a substance the body makes naturally and that is present at its highest levels in tissues such as the heart, liver, kidneys, and pancreas, where it helps cells produce energy and acts as an antioxidant. It is sold in the United States as a dietary supplement, typically in one of two forms: ubiquinone (the oxidized form) or ubiquinol (the reduced form).

For most uses the evidence is limited or inconclusive. According to NIH's National Center for Complementary and Integrative Health (NCCIH), the few studies on whether CoQ10 helps prevent heart disease have been inconclusive, and research on heart failure is also inconclusive, although there is some evidence that CoQ10 may reduce the risk of certain complications of heart surgery. NCCIH states that the overall scientific evidence does not support the idea that CoQ10 reduces muscle pain caused by statins, that the small amount of available evidence suggests it probably does not have a meaningful effect on blood pressure, and that a large NIH-funded study found CoQ10 did not improve symptoms in people with early Parkinson's disease. CoQ10 has not been shown to be of value in treating cancer, though it may reduce the risk of heart damage from one type of chemotherapy drug, and research on conditions such as ALS, Huntington's disease, and male infertility is too limited for conclusions to be drawn.

There is no established standard supplement dose, and the authoritative NIH (NCCIH) source we reviewed does not recommend a specific amount for general health. Because the evidence for most uses is limited or inconclusive, talk to your doctor or pharmacist before starting CoQ10 to discuss whether it is appropriate for you and a sensible amount, especially if you take prescription medications or have a health condition.

According to NCCIH, no serious side effects of CoQ10 have been reported, and it appears generally well tolerated. As with any supplement, discuss use with a clinician if you are pregnant or breastfeeding, have a chronic condition, are scheduled for surgery, or take other medicines, since supplement quality and individual needs vary.

Reported side effects are generally mild and may include trouble sleeping (insomnia) or digestive upset such as nausea or stomach discomfort. NCCIH reports that no serious side effects of CoQ10 have been reported.

According to NCCIH, CoQ10 may interact with the anticoagulant (blood thinner) warfarin and the diabetes drug insulin, and it may not be compatible with some types of cancer treatment. Tell your healthcare provider about all supplements you take so they can check for possible interactions.