Coenzyme Q10 (CoQ10) is a compound found naturally in the energy-producing center of the cell known as the mitochondria. CoQ10 is involved in the making of an important molecule known as adenosine triphosphate (ATP). ATP serves as the cell's major energy source and drives a number of biological processes including muscle contraction and the production of protein. CoQ10 also works as an antioxidant.

Antioxidants are substances that scavenge free radicals, damaging compounds in the body that alter cell membranes, tamper with DNA, and even cause cell death. Free radicals occur naturally in the body, but environmental toxins (including ultraviolet light, radiation, cigarette smoking, and air pollution) can also increase the number of these damaging particles. Free radicals are believed to contribute to the aging process as well as the development of a number of health problems including heart disease and cancer. Antioxidants such as CoQ10 can neutralize free radicals and may reduce or even help prevent some of the damage they cause.

CoQ10 boosts energy, enhances the immune system, and acts as an antioxidant. Clinical research suggests that using coenzyme Q10 supplements alone or in combination with other drug therapies and nutritional supplements may help prevent or treat some of the following conditions:

Heart disease

Researchers believe that the beneficial effect of CoQ10 in the prevention and treatment of heart disease is due to its ability to improve energy production in cells, inhibit blood clot formation, and act as an antioxidant. One important clinical study, for example, found that people who received daily CoQ10 supplements within 3 days of a heart attack were significantly less likely to experience subsequent heart attacks and chest pain. In addition, these same patients were less likely to die of heart disease than those who did not receive the supplements.

Heart failure (HF)

Levels of CoQ10 are low in people with congestive heart failure (HF), a debilitating disease that occurs when the heart is not able to pump blood effectively. This can cause blood to pool in parts of the body, such as the lungs and legs. Information from several clinical studies suggests that CoQ10 supplements help reduce swelling in the legs, enhance breathing by reducing fluid in the lungs, and increase exercise capacity in people with HF. Not all clinical studies agree, however. As a result, some experts conclude that CoQ10 supplements do not contribute any benefit to the usual conventional treatment for HF. More conclusive research will help resolve the debate.

High blood pressure

Several clinical studies involving small numbers of people suggest that CoQ10 may lower blood pressure. However, it may take 4 - 12 weeks before any beneficial effect is observed. More research with greater numbers of people is needed to assess the value of CoQ10 in the treatment of high blood pressure.

High cholesterol

Levels of CoQ10 tend to be lower in people with high cholesterol compared to healthy individuals of the same age. In addition, certain cholesterol-lowering drugs called statins (such as atorvastatin, cerivastatin, lovastatin, pravastatin, simvastatin) appear to deplete natural levels of CoQ10 in the body. Taking CoQ10 supplements can correct the deficiency caused by statin medications without affecting the medication's positive effects on cholesterol levels.

Diabetes

CoQ10 supplements may improve heart health and blood sugar and help manage high cholesterol and high blood pressure in individuals with diabetes. High blood pressure, high cholesterol, and heart disease are all common problems associated with diabetes. Despite some concern that CoQ10 may cause a sudden and dramatic drop in blood sugar (called hypoglycemia), two recent clinical studies of people with diabetes given CoQ10, 200 mg 2 times daily, showed no hypoglycemic response. If you have diabetes, talk to your doctor or registered dietitian before using CoQ10.

Heart damage caused by chemotherapy

Several clinical studies suggest that CoQ10 may help prevent heart damage caused by certain chemotherapy drugs (namely adriamycin or other athracycline medications). More clinical studies are needed to further evaluate the effectiveness of CoQ10 in preventing heart damage in cancer patients undergoing chemotherapy.

Heart surgery

Clinical research indicates that introducing CoQ10 prior to heart surgery, including bypass surgery and heart transplantation, can reduce damage caused by free radicals, strengthen heart function, and lower the incidence of irregular heart beat (arrhythmias) during the recovery phase.

Breast cancer

Studies of women with breast cancer suggest that CoQ10 supplements (in addition to conventional treatment and a nutritional regimen including other antioxidants and essential fatty acids) may shrink tumors, reduce pain associated with the condition, and cause partial remission in some individuals. It is important to recognize that the beneficial effects these women experienced cannot be attributed to CoQ10 alone. Additional antioxidants used in these studies include vitamins C, E, and selenium.

Periodontal (gum) disease

Gum disease is a widespread problem that is associated with swelling, bleeding, pain, and redness of the gums. Clinical studies have reported that people with gum disease tend to have low levels of CoQ10 in their gums. In a few clinical studies involving small numbers of subjects, CoQ10 supplements caused faster healing and tissue repair. CoQ10 is used in mouth rinse products for this condition. Additional studies in humans are needed to evaluate the effectiveness of CoQ10 when used together with traditional therapy for periodontal disease.

Other

Preliminary clinical studies also suggest that CoQ10 may:

• Improve immune function in individuals with immune deficiencies (such as acquired immunodeficiency syndrome or AIDS) and chronic infections (such as yeast, bacteria, and viral infections)
• Increase sperm motility leading to enhanced fertility
• Be used as part of the treatment for Alzheimer's disease and Parkinson's disease
• Reduce damage from stroke
• Boost athletic performance
• Enhance physical activity in people with fatigue syndromes
• Improve exercise tolerance in individuals with muscular dystrophy
• Improve symptoms of tinnitus, or ringing in the ears
• Be beneficial in cosmetics for healthy skin
• Delay the aging process and increase longevity

Clinical research in all of these areas is underway to determine whether CoQ10 can be safeLy and effectively used in people with these health problems and needs.

Primary dietary sources of CoQ10 include oily fish (such as salmon and tuna), organ meats (such as liver), and whole grains. Most individuals obtain sufficient amounts of CoQ10 through a balanced diet, but supplementation may be useful for individuals with particular health conditions (see Uses section) or those taking certain medications (see Interactions section).

Coenzyme Q10 is available as a supplement in several forms, including soft gel capsules, oral spray, hardshell capsules, and tablets. CoQ10 is also added to various cosmetics.

Pediatric

Use of coenzyme Q10 in children under 18 years of age is only recommended under the supervision of a health care provider.

Adult

For adults 19 years and older: The recommended dose for CoQ10 supplementation is 30 - 200 mg daily.

Coenzyme Q10 is fat-soluble so should be taken with a meal containing fat for optimal absorption. Also, taking coenzyme Q10 at night may help with the body's ability to use it.

Coenzyme Q10 may be used as an oral mouth rinse for gum disease (periodontal). Rinse with 1 teaspoonful (5 mL), 1 - 2 times daily.

Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable health care provider.

Coenzyme Q10 appears to be generally safe with no significant side effects, except occasional stomach upset. However, the safety of CoQ10 supplementation during pregnancy and breast-feeding is unknown and, therefore, should not be used during that time until more information is available.

If you are currently being treated with any of the following medications, you should not use CoQ10 without first talking to your health care provider.

Daunorubicin and doxorubicin -- Coenzyme Q10 may help to reduce the toxic effects on the heart caused by daunorubicin (Cerubidin) and doxorubicin (Adriamycin), two chemotherapy medications that are commonly used to treat several kinds of cancer. Always speak to your oncologist before taking antioxidants along with chemotherapy.

Blood pressure medications -- In a clinical study of individuals taking blood pressure medications, including diltiazem (Cardizem), metoprolol (Lopressor or Toprol), enalapril (Vasotec), and nitroglycerin (Nitrostat or Nitrobid), CoQ10 supplementation allowed the individuals to take lower dosages of these drugs. This suggests that CoQ10 may enhance the effectiveness of certain blood pressure medications, but more research is needed to verify these results.

Blood-thinning medications -- There have been reports that coenzyme Q10 may decrease the effectiveness of blood-thinning medications such as warfarin (Coumadin) or clopidigrel (Plavix), leading to the need for increased doses. Therefore, given that this medication must be monitored very closely for maintenance of appropriate levels and steady blood thinning, CoQ10 should be used with warfarin only under careful supervision by your health care provider.

Timolol -- CoQ10 supplementation may reduce the heart-related side effects of timolol drops (Betoptic), a beta-blocker medication used to treat glaucoma, without decreasing the effectiveness of the medication.

Other -- Medications that can lower the levels of coenzyme Q10 in the body include statins for cholesterol , including atorvastatin (Lipitor), lovastatin (Mevacor), pravastatin (Pravachol, and simvastatin (Zocor), fibric acid derivatives for cholesterol, including gemfibrozil (Lopid), beta-blockers for high blood pressure, such as atenolol (Tenormin), labetolol (Normodyne), metoprolol (Lopressor or Toprol), and propranolol (Inderal), and tricyclic antidepressant medications, including amitriptyline (Elavil), doxepin (Sinequan), and imipramine (Tofranil).

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