CoQ10 and Cholesterol

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CoQ10 and Cholesterol

Question:

I have been taking a supplement, CoQ10 (100 mg) for a heart condition. Recently, I read that this may affect cholesterol levels. What can you tell me about CoQ10?

Answer:

CoQ10 is the abbreviation for coenzyme Q10. Our bodies produce this chemical naturally. It exists in every active human cell and is essential for cells to work. It also acts as an antioxidant.

Some people can have lower blood levels of CoQ10, but scientists aren't sure what this means and what should be done to correct it.

Coenzyme Q10 can be taken orally. It has been suggested to treat a wide variety of conditions. Studies evaluating the use of CoQ10 in heart disease, including coronary artery disease and heart failure, have had mixed results, but tend show some benefit.

Another common use of coenzyme Q10 is for the treatment and prevention of muscle damage caused by statin drugs. Statins are prescribed to lower cholesterol, protect against damage from coronary-artery disease and prevent heart attacks. While studies show that taking a statin can sometimes decrease the amount of CoQ10 in muscle, it's not clear that the lower CoQ10 is the actual cause of statin-induced muscle pain or weakness.

Regarding coenzyme Q10 and cholesterol, people with high cholesterol levels tend to have lower than usual CoQ10 blood levels. Taking a CoQ10 supplement seems to have no significant effect on cholesterol readings.

The correct dose of CoQ10 is unknown. Studies have used doses ranging from 50 milligrams per day to 1,200 milligrams per day. The more usual doses are 100 to 600 milligrams per day, in divided doses.

Coenzyme Q10 seems to be well tolerated with minimal side effects. Some people may experience stomach discomfort, nausea or vomiting. Rare side effects include rash or itching. Other side effects may include dizziness, difficulty sleeping, irritability, headache, sensitivity to light, fatigue or flulike symptoms.

In theory, coenzyme Q10 may increase the risk of blood clots. In contrast, coenzyme Q10 may also theoretically increase the risk of bleeding in some people, based on one report that coenzyme Q10 has effects on components of the blood that are involved with forming blood clots. If you have a blood clotting disorder or a history of blood clots or if you use anticoagulants (blood thinners) or antiplatelet drugs such as warfarin (Coumadin), heparin or clopidogrel (Plavix), speak with your health care provider before using coenzyme Q10.

Howard LeWine, M.D., is chief editor of Internet Publishing at Harvard Health Publications. He is recognized as an outstanding clinician and teacher and is a recipient of the Internal Medicine Teacher of the Year award at Brigham and Women's Hospital. Dr. LeWine continues to practice Internal Medicine; most recently he became a hospitalist after practicing primary care for over 20 years.

Last updated:	July 20, 2009