What is the Evidence For Coenzyme Q10?
*Heart failure:People with heart failure have been found to have lower levels of CoQ10 in heart muscle cells. Double-blind research suggests that CoQ10 may reduce symptoms related to heart failure, such as shortness of breath, difficulty sleeping, and swelling. CoQ10 is thought to increase energy production in the heart muscle, increasing the strength of the pumping action. Recent human studies, however, haven't supported this.In one study, 641 people with congestive heart failure were randomized to receive either CoQ10 (2 mg per kg body weight) or a placebo plus standard treatment. People who took the CoQ10 had a significant reduction in symptom severity and fewer hospitalizations.In another study, 32 patients with end-stage heart failure awaiting heart transplantation received either 60 mg of CoQ10 or a placebo for 3 months. Patients who took the CoQ10 experienced a significant improvement in functional status, clinical symptoms, and quality of life, however there were no changes in echocardiogram (heart ultrasound) or in objective markers.A study randomized 55 patients with congestive heart failure to receive either 200 mg per day of CoQ10 or a placebo in addition to standard treatment. Although serum levels of CoQ10 increased in patients receiving CoQ10, CoQ10 didn't affect ejection fraction, peak oxygen consumption, or exercise duration.A longer-term study investigated the use of 100 mg of CoQ10 or a placebo in addition to standard treatment in 79 patients with stable chronic congestive heart failure. The results indicated that CoQ10 only slightly improved maximal exercise capacity and quality of life compared with the placebo.*Cardiomyopathy:Several small trials have found CoQ10 may be helpful for certain types of cardiomyopathy.
*Parkinson's disease : Lower levels of CoQ10 have also been observed in people with Parkinson's disease. Preliminary research has found that increasing CoQ10 may increase levels of the neurotransmitter dopamine, which is thought to be lowered in people with Parkinson's disease. It has also been suggested that CoQ10 might protect brain cells from damage by free radicals.A small, randomized controlled trial examined the use of 360 mg CoQ10 or a placebo in 28 treated and stable Parkinson's disease patients. After 4 weeks, CoQ10 provided a mild but significant significant mild improvement in early Parkinson's symptoms and significantly improved performance in visual function.A larger 16 month trial funded by the National Institutes of Health explored the use of CoQ10 (300, 600 or 1200 mg/day) or a placebo in 80 patients with early stage Parkinson's disease. The results suggested that CoQ10, especially at the 1200 mg per day dose, had a significant reduction in disability compared to those who took a placebo.