Is ubiquinol better than regular CoQ10?

Ubiquinol and regular CoQ10 (ubiquinone) are two forms of the same molecule. After ingestion, the body largely converts ubiquinone into ubiquinol on its own -- the active form found in the blood. In a randomised crossover study in 21 healthy older adults, the absorption of ubiquinol capsules was not measurably better than that of regular ubiquinone capsules: a difference in blood levels did exist (a factor of 1.7), but it was not statistically convincing. A smaller study using a special ubiquinol co-crystal formulation (n=12) did find a factor 2-3 higher absorption, but that involved a specific new formulation, not standard ubiquinol available in shops.

Interestingly, clinical outcomes showed that ubiquinone performs well for the heart. A review of 28 clinical studies concluded that regular CoQ10 reduced cardiovascular mortality in heart failure, whereas that effect was not demonstrated for ubiquinol. A caveat applies here: one author of that review works for a CoQ10 manufacturer. The result is nonetheless noteworthy, especially since ubiquinone appeared to achieve a comparable effect at even lower doses.

In laboratory research using human skin cells, ubiquinol outperformed ubiquinone in countering signs of ageing. But what works in a petri dish does not automatically work the same way in humans. A small study (n=20) in people with prediabetes found that ubiquinol reduced a specific type of harmful cholesterol within the treatment group, but the difference compared with the placebo group did not reach statistical significance.

There is one interaction worth keeping in mind: people who take high doses of vitamin E alongside CoQ10 may thereby lower their ubiquinol levels in the blood. This is likely because ubiquinol neutralises vitamin E radicals, and that interplay can disturb the balance.