Health News and Research
Bioavailability of Coenzyme Q10
In New Zealand, at least 10 brands of coenzyme Q10 (CoQ10) supplement are available over the counter from health food shops, pharmacies, and the Internet. Supplementation with coenzyme Q10 increases energy, wellbeing, stamina and muscle performance, strengthens the heart, and scavenges free radicals.
Coenzyme Q10 is an essential cofactor in the mitochondrial electron transport chain and also acts as an antioxidant, sparing, the α-tocopheroxyl radical. In mammals, CoQ10 is synthesized in all cells—and the diet is also a source, with meat being the biggest contributor.
There was a significant difference in bioavailability between
the seven CoQ10 brands (p<0.001), with
Q-Gel being significantly better
than any other supplement (p=0.013).
There was a significant correlation between baseline LDL concentrations and change in CoQ10 (p=0.004; R=+0.343), between total cholesterol levels and change in CoQ10 (p=0.004; R=+0.338), and also between baseline triglycerides and change in CoQ10 (p=0.035; R=+0.253). Therefore, higher LDL cholesterol or triglyceride concentrations may aid absorption of CoQ10.
We found important differences in the bioavailability of these supplements. However, the mean increase in plasma total CoQ10 of 0.41 µmol/L equates to about 0.7 mg of CoQ10 being absorbed into the blood from the 150 mg supplied. This can be compared to the normal diet in which CoQ10 is limited to about 3 to 5 mg per day, mainly via the consumption of meats rather than fruits and vegetables.
Because CoQ10 is lipid soluble, it is likely that administration as a dispersion (or solubilized) in oil will aid absorption, as found in our study. The high bioavailability of Q-Gel compared to other coenzyme Q10 supplement brands supports the findings of Chopra et al who found the absorption of Q-Gel to be 319% better than that from a standard softgel capsule containing Q10 in oil, after 3 weeks of a daily 120 mg dose. Chopra et al also found the absorption from powder-filled hardshell capsules and powder-based tablets to be higher (125% and 128% respectively) than that from a standard softgel capsule.
Miles et al found the increase of plasma total CoQ10 by ‘solubilized’ supplemental CoQ10 to be 858%–1058% higher than that from a dry powder formulation. Furthermore, Wahlqvist et al found that the bioavailability of CoQ10 in a complex micelle emulsion (in a soft gelatine capsule) was 927% higher than a crystalline CoQ10 supplement with magnesium stearate (as an excipient and a hard gelatine capsule).
Thus it is clear that there are important differences. There is at least a four-fold variation in the increase in plasma CoQ10 achieved by different supplements, and some people get no increase when they take the less effective supplements at typical doses.
There are important differences in bioavailability between the available CoenzymeQ10 supplements and also significant inter-individual differences. We therefore recommend monitoring of plasma CoQ10 levels during supplementation, and that differences in bioavailability are considered when selecting a supplement. In this study, the Q-gel brand showed significantly better bioavailability than the six other CoQ10 supplements tested.
Sarah Molyneux, Christopher Florkowski, Michael Lever, Peter
George. The bioavailability of coenzyme Q10 supplements
available in New Zealand differs markedly. Journal of the New Zealand Medical Association,
08-October-2004, Vol 117 No 1203.
Key concepts: hydrosoluble coenzyme Q10 Q-Gel, coq10, blood pressure, hypertension