Comparison Study of Plasma Coenzyme Q(10) Levels in Healthy Subjects Supplemented With Ubiquinol Versus Ubiquinone

The bioavailability of the reduced form of coenzyme Q(10) (ubiquinol) was compared to oxidized coenzyme Q(10) (ubiquinone) with identical soft gel capsule excipients by measuring steady state plasma coenzyme Q(10) (CoQ(10)) levels in 12 healthy volunteers. After baseline levels of ubiquinol, ubiquinone, total CoQ(10), alpha-tocopherol, and total cholesterol were obtained, follow-up lab work was performed after 4 weeks of 200 mg/day of ubiquinone, after 4 weeks washout, and after 4 weeks of 200 mg/day of ubiquinol. Plasma total CoQ(10) increased from 0.9 to 2.5 mu g/mL (P<0.001) after 4 weeks of ubiquinone and increased from 0.9 to 4.3 mu g/mL (P<0.001) after 4 weeks of ubiquinol. Total CoQ(10)/cholesterol ratio increased from 0.2 to 0.7 mu mol/mmol after 4 weeks of ubiquinone and increased from 0.2 to 1.2 mu mol/mmol after 4 weeks of ubiquinol. Both the increase in plasma CoQ(10) and the increase in CoQ(10)/cholesterol ratio were significantly better after ubiquinol (P<0.005 and P<0.001, respectively) than after ubiquinone indicating superior bioavailability. Plasma ubiquinol/total CoQ(10) ratio increased from baseline during ubiquinol supplementation (P<0.005) and remained unchanged after ubiquinone supplementation. No side effects were noted in this study.