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 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. A growing body of 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 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.

Congestive Heart Failure (CHF)

Levels of CoQ10 are low in people with CHF, 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 many research 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 CHF. Not all studies agree, however. As a result, some experts conclude that CoQ10 supplements do not contribute any benefit to the usual conventional treatment for CHF. More conclusive research will help resolve the debate.

High Blood Pressure

Several studies involving small numbers of people suggest that CoQ10 may lower blood pressure. However, it may take 4 to 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 studies of people with diabetes given CoQ10 two times per day showed no hypoglycemic response. The safest bet if you have diabetes is to talk to your doctor or registered dietitian about the possible use of CoQ10.

Heart Damage caused by Chemotherapy

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

Heart Surgery

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. Studies have shown that people with gum disease tend to have low levels of CoQ10 in their gums. In a few studies involving small numbers of subjects, CoQ10 supplements caused faster healing and tissue repair. Additional studies are needed to evaluate the effectiveness of CoQ10 when used together with traditional therapy for periodontal disease.

Other

Preliminary studies also suggest that CoQ10 may:

• Improve immune function in individuals with immune deficiencies (such as AIDS) and chronic infections (such as yeast and other viral infections)
• Increase sperm motility leading to enhanced fertility
• Be used as part of the treatment for Alzheimer'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

Research in all of these areas is underway to determine whether CoQ10 can be safety and effectively used in people with these health problems.

Primary dietary sources of CoQ10 include oily fish, 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 softgel capsules, oral spray, hardshell capsules, and tablets.

Pediatric

There are no known scientific reports on the pediatric use of CoQ10. Therefore, use of CoQ10 supplements is not currently recommended for children.

Adult

The general recommended dose for CoQ10 supplementation is 30 to 60 mg daily. Higher doses have been used in studies and may be recommended for the following conditions:

• Congestive heart failure: 50 to 150 mg a day
• High blood pressure: 50 to 150 mg a day
• To enhance athletic performance: 60 mg a day for 4 to 8 weeks
• Heart attack: 120 mg a day for 28 days after the heart attack
• Breast cancer: 400 mg per day for potential prevention and treatment

Coenzyme Q10 is fat-soluble so should be taken with a meal containing fat for optimal absorption.

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

Daunorubicin and Doxorubicin
Coenzyme Q10 may help to reduce the toxic effects on the heart caused by daunorubicin and doxorubicin, two chemotherapy medications that are commonly used to treat a variety of cancers.

Blood Pressure Medications
In a study of individuals taking blood pressure medications (including diltiazem, metoprolol, enalapril, and nitrate), 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.

Warfarin
There have been reports that coenzyme Q10 may decrease the effectiveness of blood-thinning medications such as warfarin, 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 only be used with warfarin under careful supervision by your healthcare provider.

Timolol
CoQ10 supplementation may reduce the heart-related side effects of timolol drops, 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 (atorvastatin, cerivastatin, lovastatin, pravastatin, simvastatin), fibric acid derivatives for cholesterol (specifically, gemfibrozil), beta-blockers for high blood pressure (such as atenolol, labetolol, metoprolol, and propranolol), and tricyclic antidepressant medications (including amitriptyline, amoxapine, clomipramine, desipramine, doxepin, imipramine, nortriptyline, protriptyline, and trimipramine).

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