Shop products for Coenzyme Q10 
What is it?
Coenzyme Q10 (CoQ10) is also called ubiquinone, a name that signifies its ubiquitous (widespread) distribution in the human body. CoQ10 is used by the body to transform food into adenosine triphosphate (ATP), the energy on which the body runs.
Where is it found?
CoQ10 is found primarily in fish and meat, but the amounts in food are far less than what can be obtained from supplements.
What do the advocates say?*
Because CoQ10 plays a major role in fat and energy metabolism, it may be beneficial to athletes who are expending a lot of calories. However, CoQ10 has not been fully investigated in regards to its effect on athletic performance.
How much is usually taken by athletes?
Strenuous physical activity lowers blood levels of coenzyme Q10 (CoQ10).1 However, the effects of CoQ10 on how the healthy body responds to exercise have been inconsistent, with several studies finding no improvement.2 3 4 5 A few studies, using at least four weeks of CoQ10 supplementation at 60 to 100 mg per day, have reported improvements in measures of work capacity ranging from 3 to 29% in sedentary people and from 4 to 32% in trained athletes.6 However, recent double-blind and/or placebo-controlled trials in trained athletes, using performance measures such as time to exhaustion and total performance, have found either no significant improvement or significantly poorer results in those taking CoQ10.7 8 9
Are there any side effects or interactions?
Congestive heart failure patients who are taking CoQ10 should not discontinue taking CoQ10 supplements unless under the supervision of a doctor.
An isolated test tube study reported that the anticancer effect of a certain cholesterol-lowering drug was blocked by addition of CoQ10.10 So far, experts in the field have put little stock in this report because its results have not yet been confirmed in animal, human, or even other test tube studies. The drug used in the test tube is not used to treat cancer, and preliminary information regarding the use of high amounts of CoQ10 in humans suggests the possibility of anticancer activity.11 12 13
Are there any drug
interactions?
Certain medicines may interact with coenzyme Q10. Refer to drug interactions for a list of those medicines.
*Athletes and fitness advocates may claim benefits for coenzyme Q10 based on their personal or professional experience. These are individual opinions and testimonials that may or may not be supported by controlled clinical studies or published scientific articles on coenzyme Q10. For more complete and detailed information, including references and safety information, see Coenzyme Q10 as a nutritional supplement.
References
1. Kaikkonen J, Nyyssonen K, Tuomainen TP, et al. Determinants of plasma coenzyme Q10 in humans. FEBS Lett 1999;443:163–6 [review].
2. Overvad OK, Diamant B, Holm L, et al. Efficacy and safety of dietary supplementation containing Q10. Ugeskr Laeger 1997;159:7309–15 [review] [in Danish].
3. Zuliani U, Bonetti A, Campana M, et al. The influence of ubiquinone (Co Q10) on the metabolic response to work. J Sports Med Phys Fitness 1989;29:57–62 [review].
4. Bonetti A, Solito F, Carmosino G, et al. Effect of ubidecarenone oral treatment on aerobic power in middle-aged trained subjects. J Sports Med Phys Fitness 2000;40:51–7.
5. Weston SB, Zhou S, Weatherby RP, Robson SJ. Does exogenous coenzyme Q10 affect aerobic capacity in endurance athletes? Int J Sport Nutr 1997;7:197–206.
6. Bucci L. Nutrients as ergogenic aids for sports and exercise. Boca Raton, FL: CRC Press, 1993, 54–7 [review].
7. Snider IP, Bazzarre TL, Murdoch SD, et al. Effects of coenzyme athletic performance system as an ergogenic aid on endurance performance to exhaustion. Int J Sport Nutr 1992;2:272–86.
8. Malm C, Svensson M, Ekblom B, et al. Effects of ubiquinone-10 supplementation and high intensity training on physical performance in humans. Acta Physiol Scand 1997;161:379–84.
9. Laaksonen R, Fogelholm M, Himberg JJ, et al. Ubiquinone supplementation and exercise capacity in trained young and older men. Eur J Appl Physiol 1995;72:95–100.
10. Larsson O. Effects of isoprenoids on growth of normal human mammary epithelial cells and breast cancer cells in vitro. Anticancer Res 1994;114:123–8.
11. Lockwood K, Moesgaard S, Folkers K. Partial and complete regression of breast cancer in patients in relation to dosage of coenzyme Q10. Biochem Biophys Res Commun 1994;199:1504–8.
12. Lockwood K, Moesgaard S, Yamamoto T, Folkers K. Progress on therapy of breast cancer with vitamin Q10 and the regression of metastases. Biochem Biophys Res Commun 1995;212:172–7.
13. Judy WV. Nutritional intervention in cancer prevention and treatment. American College for Advancement in Medicine Spring Conference, Ft. Lauderdale, FL. May 3, 1998.
