Understanding the Difference Between Ubiquinol and Ubiquinone: Key Insights for Fertility and Health

When sourcing Coenzyme Q10 (CoQ10) for fertility, mitochondrial function and overall health, it is essential to understand the differences between ubiquinol and ubiquinone. Both are forms of CoQ10, but they differ in chemical structure, absorption rates, antioxidant properties and their ability to support fertility. This distinction is especially important for those trying to optimise their reproductive health.

"15 years ago, when I became interested in ubiquinol there was limited evidence on how CoQ10 could support fertility. But thanks to ongoing research, we now have a clearer understanding, which has led to more informed decisions in supplement sourcing." — Zita West

Here is a breakdown of the key differences between the two forms:

1. Chemical structure and active form

Ubiquinol is the reduced (active) form of CoQ10. It is electron-rich and ready to act as a powerful antioxidant in the body, protecting cells from oxidative damage immediately upon absorption.

Ubiquinone is the oxidised form of CoQ10. It needs to be converted into ubiquinol by the body before it can become effective in its antioxidant and energy-boosting roles. This conversion step is what makes ubiquinone less efficient, particularly as we age.

2. Absorption and bioavailability

Ubiquinol is the most bioavailable and absorbable form of CoQ10. Studies show that Kaneka Ubiquinol, used in Zita West's CoQ10 supplement, has significantly higher absorption compared to ubiquinone. This makes it especially beneficial for individuals over 35, as the body's ability to convert ubiquinone into ubiquinol declines with age.

Ubiquinone requires conversion into ubiquinol before it can be fully utilised. As we age or in certain health conditions, this conversion becomes progressively less efficient, meaning a smaller proportion of each dose reaches the cells where it is needed.

3. Antioxidant properties

Ubiquinol acts as a potent antioxidant, neutralising harmful free radicals that can damage cells including eggs and sperm. Oxidative stress is one of the key drivers of declining egg quality and sperm motility, making antioxidant protection particularly important for anyone trying to conceive.

Ubiquinone also has antioxidant properties but must first be converted into ubiquinol to provide maximum protection. In younger individuals with efficient conversion, the practical difference may be smaller. In those over 35, the gap widens considerably.

4. Energy production and mitochondrial support

Both forms of CoQ10 play an essential role in energy production within the mitochondria. Ubiquinol is the active form that directly contributes to ATP production, the energy currency needed for cellular function. Eggs in particular are among the most energy-intensive cells in the body and depend on strong mitochondrial function for the cell divisions that determine embryo quality.

Ubiquinone must first be converted to ubiquinol to contribute to energy production, making it less efficient for those with reduced conversion ability, particularly older adults.

5. Fertility and supplementation

Ubiquinol is particularly recommended for individuals looking to improve fertility, support energy levels and promote cellular health. For both male and female fertility, Kaneka Ubiquinol helps reduce oxidative stress, support mitochondrial function and improve the quality of eggs and sperm. It is relevant for those trying to conceive naturally and for those preparing for IVF or other assisted reproductive technologies.

Ubiquinone still offers benefits, but its conversion to the active form is less efficient in individuals over 35 or those with compromised conversion ability, making ubiquinol the more reliable choice for fertility support.

Why Zita West chooses Kaneka Ubiquinol

"For a long time now I have encouraged women and men to use Kaneka Ubiquinol in their supplements because it is the best-absorbed form of CoQ10." — Zita West

Kaneka Ubiquinol has been extensively researched and shown to be among the most bioavailable and effective forms of CoQ10 supplementation available. By using Kaneka Ubiquinol, Zita West ensures products deliver maximum support for:

• Egg quality. Read more about CoQ10 and egg health here.
• Sperm health. Read more about CoQ10 and sperm health here.
• Mitochondrial function and cellular energy production
• Reducing oxidative damage in reproductive cells

Why ubiquinol matters for male and female fertility

Both male and female fertility benefit from ubiquinol's antioxidant and mitochondrial support. For women, it helps protect eggs from oxidative damage and supports the energy production required for fertilisation and early embryo development. For men, ubiquinol supports sperm motility and count, increasing the chances of successful conception.

With the body's ability to convert ubiquinone into ubiquinol diminishing with age, supplementing directly with the active form ensures maximum support — particularly for women over 35. Read our guide to CoQ10 and fertility after 40 here.

FAQs: ubiquinol vs ubiquinone

Is ubiquinol the same as CoQ10?

Yes. Ubiquinol is one of the two main forms of CoQ10. The other is ubiquinone. Both are the same molecule in different states — ubiquinol is the active, reduced form, and ubiquinone is the oxidised form that the body must convert before use.

Which is better for fertility, ubiquinol or ubiquinone?

For most people, and particularly those over 35 or preparing for IVF, ubiquinol is the better choice due to its superior bioavailability and the fact that it does not require conversion. Zita West uses Kaneka Ubiquinol in our CoQ10 formula for this reason.

Why does age matter when choosing between ubiquinol and ubiquinone?

The body's ability to convert ubiquinone into ubiquinol declines with age, particularly from the mid-thirties onward. This means that for older individuals, a larger proportion of a ubiquinone supplement may be lost in the conversion process, reducing the effective dose that reaches reproductive cells.

What is Kaneka Ubiquinol?

Kaneka Ubiquinol is a specific, patented form of ubiquinol manufactured in Japan by Kaneka Corporation. It is one of the most bioavailable forms of CoQ10 available and has been used in multiple clinical fertility studies. It is the form used in Zita West Kaneka Ubiquinol CoQ10.

How much ubiquinol should I take for fertility?

Dosage recommendations vary depending on age, sex and whether you are preparing for natural conception or IVF. For a full breakdown, read our CoQ10 dosage guide here.

How long should I take ubiquinol before trying to conceive?

Most research recommends at least 3 months of consistent supplementation, with 6 months associated with the best outcomes for both egg and sperm quality. The 120 capsule size gives you a full 3 months at 200mg per day. For full timing guidance, read our timing guide here.

Can men take ubiquinol for fertility?

Yes. Sperm cells are highly vulnerable to oxidative stress and rely on mitochondrial energy for motility. Ubiquinol supports both of these areas. Male partners should follow the same 3 to 6 month supplementation timeline. Zita West Vitamen includes CoQ10 as part of a broader male fertility nutrient profile.

This content is for educational purposes only and is not intended to diagnose, treat, or replace medical advice. Always consult your healthcare provider before starting any new supplement.