The Ubiquinol form of CoQ10 is vital to a healthy body.
Conventional CoQ10, also called ubiquinone, is the fully oxidized form of CoQ10. When you take this type of CoQ10 supplement, it must first be converted to Ubiquinol in order to assist with the production of cellular energy.
Converting conventional CoQ10 (ubiquinone) into Ubiquinol becomes harder and less efficient by age 40. Ubiquinol supplements require no further conversion inside the body, making them a more beneficial CoQ10 option for many people over the age of 40.
This article explains more about the two main forms of CoQ10.