The topic of this thread is anything related to coenzyme Q10 and ubiquinol, but I'll start off with some questions. When CoQ10 is measured in the body, are they measuring ubiquinone or ubiquinol? My understanding is that ubiquinone (which most coenzyme q10 supplements are unless labeled ubiquinol) needs to be converted to ubiquinol to be used. That leads me to my second question What factors affect how well a person converts ubiquinone to ubiquinol? I read something about people over 40 recommended to take ubiquinol instead of ubiquinone. When someone naturally produces coenzyme q10 do they produce ubiquinone and then need to convert it to ubiquinol?