Ubiquinol vs ubiquinone (CoQ10)

At a glance: ubiquinol vs ubiquinone

Ubiquinone and ubiquinol are the oxidised and reduced forms of the same molecule, coenzyme Q10. Ubiquinol carries two extra hydrogen atoms, so the two differ by only about 0.24 % in molar mass. The practical gap between ubiquinol and ubiquinone lies elsewhere. Ubiquinol oxidises to ubiquinone on contact with air, and its EU novel-food status must be checked separately. This page compares the two as manufacturing materials, not their physiology.

Content per gram and label-claim arithmetic

The calculation uses the molar masses: 863.3 g/mol for ubiquinone and 865.36 g/mol for ubiquinol. The conversion factor is 865.36 ÷ 863.3 = 1.0024. Its inverse, 0.9976, converts ubiquinol mass into ubiquinone equivalents.

Example 1: a claim of 100 mg ubiquinol per serving. Weigh 100 mg of pure ubiquinol. Expressed as ubiquinone, this equals 100 × 0.9976 = 99.8 mg.

Example 2: a claim of 200 mg coenzyme Q10, expressed as ubiquinone. With ubiquinone, weigh 200 mg of pure material. With ubiquinol, weigh 200 × 1.0024 = 200.5 mg.

These are pure-substance figures. Commercial materials, ubiquinol in particular, are often supplied diluted or stabilised. Divide the pure figure by the assay on the certificate of analysis: required mass = claim ÷ (assay % ÷ 100). Then add any overage your stability data justifies; the overage calculator does this step. The molar correction is small next to the assay and overage corrections.

Which form the label declares, and on which basis, is a regulatory question. See the EU section below.

Solubility, taste and processing

Both forms are lipophilic and practically insoluble in water. For softgels they are dissolved or suspended in an oil carrier. For hard capsules and tablets ubiquinone is used as a dry powder or a formulated powder grade. The softgels, capsules and tablets guides cover format constraints.

Ubiquinone is a crystalline powder with a low melting point. Heat from granulation, drying or compression friction can soften it, so keep process temperatures low. It is also light sensitive, which favours opaque capsules and packaging. The specification sheet states the melting range and storage conditions.

Ubiquinol is the more demanding material. Exposure to oxygen converts it to ubiquinone, so a batch can drift towards the oxidised form during processing and storage. Common measures are limiting air exposure during mixing and filling, inert-gas blanketing, antioxidants in the fill, and oxygen-barrier packaging. Stability studies should quantify both forms separately, not only total coenzyme Q10.

Taste rarely limits either form, because both usually go into capsules or softgels. In chewables or gummies the oily, coloured character of the material needs masking and even dispersion.

EU regulatory status

Neither form is a vitamin or mineral. Annexes I and II of Directive 2002/46/EC therefore do not list them. The Directive’s harmonised rules on permitted forms cover only vitamins and minerals. Use of other substances such as coenzyme Q10 in food supplements is governed by national rules, which differ by member state. Member states may require notification or set maximum amounts.

Novel-food status must be checked for each form under Regulation (EU) 2015/2283. A food is novel if it was not used for human consumption to a significant degree in the EU before 15 May 1997 and falls within at least one of the categories listed in Article 3(2)(a). For ubiquinone, confirm its status for use in food supplements in the Commission’s Novel Food Catalogue and with national authorities.

For ubiquinol, check whether the Union list of novel foods contains an entry that covers it. If it does, the material must match the specification in that entry. The entry may also set conditions of use and specific labelling requirements, including the designation on the label. Check whether data protection limits the authorisation to a named applicant. The novel food guide explains these checks.

Label naming and quantity declaration follow Regulation (EU) No 1169/2011, Articles 6, 8 and 9 of Directive 2002/46/EC and the labelling guide. For claim wording, consult the EU Register of nutrition and health claims and the health-claims guide.

Choosing between them

• Format. Dry tablets and powder-filled capsules suit ubiquinone. Softgels and oil fills with oxygen control suit either form.
• Stability programme. Ubiquinol needs oxygen control through processing and packaging, and a method that quantifies both redox forms.
• Market by market. Ubiquinol requires a novel-food check and compliance with any Union list conditions. Both forms also need checking against national rules in each target country.
• Label basis. Decide whether the claim states ubiquinol or total coenzyme Q10, and on which molar basis.
• Cost. Compare cost per milligram of coenzyme Q10 after assay correction, using the figures in each quote.

Combining both forms is mostly a matter of honest specification. A ubiquinol product will usually contain some ubiquinone by the end of shelf life. Set the release and shelf-life specifications to state whether the claim covers ubiquinol alone or total coenzyme Q10. Deliberate blends follow the same rule, with each form declared consistently.

SoleChem sends the specification sheet and certificate of analysis with its quote. Ask for the grade you need in the quote form. Other actives in this family are under Coenzymes & Longevity Actives.