GNC Preventive Nutrition CoQ-10 100mg Softgel Capsules are now 40% Smaller. CoQ10 is a naturally-occuring compound found in every cell in the body. CoQ10"s alternate name, ubiquinone, comes from the word ubiquitous, which means "found everywhere." CoQ10 plays a key role in producing energy in the mitochondria, the part of a cell responsible for the production of energy in the form of ATP(Adenosine TriPhosphate). It is known for its antioxidant properties and helps support heart and blood vessel function.