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Coenzyme Q10 (CoQ10) is a substance similar to a vitamin. It is found in every cell of the body. Your body makes CoQ10, and your cells use it to produce energy your body needs for cell growth and maintenance. It also functions as an antioxidant, which protects the body from damage caused by harmful molecules. CoQ10 is naturally present in small amounts in a wide variety of foods, but levels are particularly high in organ meats such as heart, liver, and kidney, as well as beef, soy oil, sardines, mackerel, and peanuts.
Coenzymes help enzymes work to digest food and perform other body processes, and they help protect the heart and skeletal muscles.
CoQ10 is available in Canada as a natural health product. It is also known as Q10, vitamin Q10, ubiquinone, or ubidecarenone.
Many claims are made about CoQ10. It is said to help heart failure, as well as cancer, muscular dystrophy, and periodontal disease. It is also said to boost energy and speed recovery from exercise. Some people take it to help reduce the effects certain medicines can have on the heart, muscles, and other organs.
If you have heart failure, talk to your doctor before you take any natural health product. There's no strong evidence that vitamins or other natural health products can help treat heart failure. They are used along with medical heart failure treatments, not instead of treatment.
But you may still hear about CoQ10 supplements and heart failure. CoQ10 has not been shown definitely to relieve heart failure symptoms. Only some of the studies of coenzyme Q10 showed that it helps heart failure symptoms.footnote 1
In 1961, scientists saw that people with cancer had little CoQ10 in their blood. They found low CoQ10 blood levels in people with myeloma, lymphoma, and cancers of the breast, lung, prostate, pancreas, colon, kidney, and head and neck. Some research has suggested that CoQ10 helps the immune system and may be useful as a secondary treatment for cancer.
But the U.S. National Cancer Institute (NCI) rates the strength of the evidence for CoQ10 and cancer as weak.footnote 2
Research does not support a helpful effect of CoQ10 in periodontal (gum) disease, muscular dystrophy, or exercise recovery.
Taking 100 mg a day or more of CoQ10 has caused mild insomnia in some people. And research has detected elevated levels of liver enzymes in people taking doses of 300 mg per day for long periods of time. Liver toxicity has not been reported.
Other reported side effects include rashes, nausea, upper abdominal pain, dizziness, sensitivity to light, irritability, headache, heartburn, and fatigue.
Medicines for high cholesterol (statins) and medicines that lower blood sugar cause a decrease of CoQ10 levels and reduce the effects of CoQ10 supplements. CoQ10 can reduce the body's response to the blood thinner (anticoagulant) medicine warfarin (Coumadin) and can decrease insulin requirements in people with diabetes.
The Natural and Non-Prescription Health Products Directorate (NNHPD), within the Health Products and Food Branch of Health Canada, regulates natural health products in Canada. Natural health products, including CoQ10, must be reviewed and approved by the NNHPD before they can be sold in Canada.
Always tell your doctor if you are using a natural health product or if you are thinking about combining a natural health product with your conventional medical treatment. It may not be safe to forgo your conventional medical treatment and rely only on a natural health product. This is especially important for women who are pregnant or breastfeeding.
When using natural health products, keep in mind the following:
CitationsCoenzyme Q10 (2006). Medical Letter on Drugs and Therapeutics, 48(1229): 19–20. National Cancer Institute (2012). Coenzyme Q10 (PDQ) – Health Professional Version. Available online: http://cancer.gov/cancertopics/pdq/cam/coenzymeQ10/healthprofessional. Other Works ConsultedCoenzyme Q10 (2006). Medical Letter on Drugs and Therapeutics, 48(1229): 19–20.
Current as of: September 23, 2020
Author: Healthwise StaffMedical Review: Adam Husney MD - Family MedicineBrian D. O'Brien MD - Internal MedicineKathleen Romito MD - Family Medicine
Current as of: September 23, 2020
Author: Healthwise Staff
Medical Review:Adam Husney MD - Family Medicine & Brian D. O'Brien MD - Internal Medicine & Kathleen Romito MD - Family Medicine
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