Coenzyme Q10 is present as both ubiquinone (oxidized form) and ubiquinol (reduced form) in the human body. The human body converts ubiquinone to ubiquinol and then uses it to support metabolic functions. Though both forms can be considered for supplementation, studies show that taking ubiquinol as supplements makes it easier for assimilation especially when it is taken to bridge age-related deficiency (12).