Coenzyme Q10 (CoQ10) is a lipid-soluble, vitamin-like compound synthesized by the body from mevalonate and tyrosine. CoQ10 plays a crucial role in the production of adenosine triphosphate (ATP) in mitochondria, and serves as a potent endogenous (i.e., produced in the body) antioxidant capable of neutralizing free radicals in lipid structures.[1][2][3]
While the body naturally produces CoQ10, it can also be obtained from supplements or specific foods (refer to the question “What are the main sources of coenzyme Q10?” for more details). CoQ10 exists in either its oxidized form (ubiquinone) or its reduced form (ubiquinol), with the body interchanging the two depending on the cell’s oxidative state.[2][1] The ubiquinol/ubiquinone ratio is often used as an indicator to measure the body’s response to oxidative stress. A low ubiquinol and high ubiquinone ratio may suggest ineffective conversion between the two, potentially indicating decreased antioxidant activity.[4]