Your body naturally produces CoQ-10, also known as coenzyme Q-10. It helps your cells produce energy and functions as an antioxidant to help protect them from potentially harmful chemicals. Some people advocate use of CoQ-10 supplements for various medical conditions based on its functions in the body. The strongest evidence of benefit for CoQ-10 supplementation relates to effects in heart failure, high blood pressure and reducing side effects of cholesterol-lowering statin drugs, although use is not routinely recommended.
Congestive Heart Failure
Weakening or disease of the heart muscle can eventually lead to congestive heart failure. With this condition, the pumping ability of the heart cannot keep up with the demands of the body. The heart has a relatively high CoQ-10 requirement because of its high energy needs.
An analysis of 13 clinical trials testing the effectiveness of CoQ-10 supplementation in people with congestive heart failure was published in the February 2013 issue of "The American Journal of Clinical Nutrition." Coenzyme Q-10 supplementation from 60 to 300 mg daily for 4 to 24 weeks was found to increase heart pumping capacity and reduce disease severity. The authors concluded, however, that additional larger studies are still needed to determine potential benefits of CoQ-10 supplements for heart failure.
Some types of heart and blood vessel disease may cause a loss of artery flexibility, which can increase blood pressure. An analysis of 5 studies testing the effectiveness of CoQ-10 to increase artery flexibility was published in the April 2012 issue of "Atherosclerosis." Giving people CoQ-10 at doses of 150 to 300 mg daily for 4 to 12 weeks was found to increase artery flexibility.
In people with high blood pressure, similar doses of CoQ-10 were also found to lower blood pressure without producing side effects, according to an analysis of 12 clinical studies published in the April 2007 issue of "Journal of Human Hypertension." As of 2013, however, CoQ-10 supplements are not recommended as part of standard treatment for people with high blood pressure.
Statin Therapy Side Effects
Your body requires normal cholesterol production to make CoQ-10. The use of cholesterol-lowering statin drugs, which inhibit cholesterol production, may also inhibit CoQ-10 production. Muscle pain and weakness are possible side effects in people receiving statin therapy.
A review of clinical trials testing the effectiveness of CoQ-10 in relieving muscle symptoms in people receiving statin therapy was published in the June 12, 2007 issue of the "Journal of the American College of Cardiology." Although the evidence is not conclusive, the authors suggest that about 200 mg of CoQ-10 daily may raise blood CoQ-10 levels and help alleviate muscle symptoms in people taking large statin doses. The authors note, however, that routine use of CoQ-10 cannot be recommended for people taking statins as there is insufficient proof of benefit.
CoQ-10 has other theoretical health benefits, although evidence for proven effectiveness in people is lacking. For example, CoQ-10 may function as an antioxidant and help prevent damage to cells from chemicals known as free radicals. It has been promoted for helping to prevent or treat conditions such as Parkinson disease, breast cancer and male infertility. However, as of 2013, there is no proof that supplemental CoQ-10 is beneficial for these conditions.
Coenzyme Q-10 supplements are relatively safe but should be used under medical supervision. A typical daily dose is 100 to 200 mg, divided into equal portions. Possible side effects of supplemental CoQ-10 include gastrointestinal upset, allergic rash and headache. CoQ-10 may also interact with some prescription medications.