Coenzyme Q 10 (CoQ 10), also known as ubiquinone, is a major part of the body's mechanism for producing energy. The name of this supplement comes from the word ubiquitous, which means "found everywhere." Indeed, CoQ 10 is found in every cell in the body. It plays a fundamental role in the mitochondria, the parts of the cell that produce energy from glucose and fatty acids.

Japanese scientists first reported therapeutic properties of CoQ 10 in the 1960s. Some evidence suggests that CoQ 10 might assist the heart during times of stress on the heart muscle, perhaps by helping it use energy more efficiently.

CoQ 10's best-established use is for congestive heart failure, but the evidence that it works is not entirely consistent. Ongoing research suggests that it may also be useful for other types of heart problems, Parkinson's disease, and several additional illnesses. It is generally used in addition to, rather than instead of, standard therapies.

CoQ 10 supplementation might also be of value for counteracting side effects of certain prescription medications.

Every cell in your body needs CoQ 10, but there is no dietary requirement as the body can manufacture CoQ 10 from scratch.