Coenzyme Q-10 belongs to a family of substances called ubiquinones. These compounds are lipophilic, water-insoluble substances involved in electron transport and energy production within the mitochondria. In this capacity, coenzyme Q-10 facilitates the conversion of the energy released through glycolysis into ATP (adenosine triphospate). Coenzyme Q-10 is also a powerful antioxidant, facilitating the removal of destructive free radicals from the mitochondrial environment. Coenzyme Q-10 is believed to provide a sparing effect on vitamin E. Virtually every cell of the human body requires coenzyme Q-10, with heart muscle and the liver having the greatest concentration since their mitochondrial contest is the greatest in the body.
Deficiency is poorly understood, but may be caused by synthesis problems in the body rather than insufficiency in the diet. It is now established that many patients on statin drugs (cholesterol lowering medications and HMG CoA Reductase Inhibitors) have lowered coenzyme Q-10 levels and are at increased risk for deficiency. Many cardiologists routinely utilize coenzyme Q-10 for treating congestive heart failure. Low blood levels have been reported in people with heart failure, cardiomyopathies, gingivitis (an inflammation of the gums), morbid obesity, hypertension, muscular dystrophy, AIDS and in some patients on peripheral dialysis. Aging is also associated with lower coenzyme Q-10 levels. Some studies have indicated that high doses of coenzyme Q-10 are useful in arresting Parkinson’s disease and the treatment of Alzheimer’s disease. The most common deficiency symptoms include angina and fatigue.
Coenzyme Q-10 is in every plant and animal cell. However, the amount of coenzyme Q-10 is probably insufficient to produce the clinical effects associated with therapy. The richest dietary sources of coenzyme Q-10 are fish and red meat. The best supplement preparations are soft- gelatin capsules that contain coenzyme Q-10 in an oil base. Capsules range in dosages from 10 to 250 mg. Toxicity is not known, but doses greater than 250 mg can be associated with nausea and diarrhea.
Pregnant women and nursing mothers should avoid supplementing with coenzyme Q-10 because long-term safety studies have yet to be completed. Patients with congestive heart failure on coenzyme Q-10 therapy should not discontinue the treatment without physician approval.