Vitamin C Quality and Labeling Standard
JHFC-S-021 Enacted: 6 September 2026 / Effective: the same day
Japan Certified Health Food Council (JHFC) — English translation of the standard. In case of discrepancy the Japanese text prevails. Japanese original
Japan Certified Health Food Council (JHFC)
Enacted: 6 September 2026 / Effective: the same day
Preamble (Rationale for Enactment)
Vitamin C raw materials may contain ascorbic acid, its salts, or its derivatives, and the amount of a compound does not necessarily equal the vitamin C equivalent amount. In aqueous solution, vitamin C is affected by light, oxygen, heat, metal ions, and pH, and the amount added during manufacture alone cannot substantiate the labeled amount at the end of shelf life. This Standard is established to clarify chemical forms, conversion bases, differentiation from oxidation products, and stability in the product.
Article 1 (Purpose)
The purpose of this Standard is to evaluate the validity of raw material identity, content by form, oxidation control during manufacture, quantification, labeling units, storage, and information on precautions for intake for health foods containing vitamin C.
Article 2 (Scope)
This Standard applies to oral products containing ascorbic acid, ascorbate salts, or other compounds used as sources of vitamin C. Where derivatives are used, application shall be limited to those for which a scientific basis is available for converting the amount of the compound to a vitamin C amount.
Article 3 (Terms and Definitions)
- 1. Ascorbic acid form: The chemical form present in a raw material as the free acid, a salt, or a derivative.
- 2. Vitamin C equivalent amount: The amount expressed as ascorbic acid on the basis of the molecular composition of each form and a valid conversion basis.
- 3. Oxidized components: Components formed from ascorbic acid during storage or processing that are to be treated separately in the adopted analytical method.
- 4. Guaranteed amount at the end of shelf life: The amount subject to labeling that is verified under the labeled storage conditions and at the end of the labeled shelf life of the product.
Article 4 (Requirements)
- 1. Raw material specifications shall state the chemical name, elements constituting the salt, derivatizing groups, origin, and carriers used in the preparation. The form shall be verified using chromatographic or spectroscopic documentation involving reference standards or other such documentation, and ascorbic acid and its salts or derivatives shall not be treated as equivalent amounts on the basis of names alone. The business operator shall establish identity and purity specifications for each form and shall present their basis.
- 2. Where a vitamin C equivalent amount is labeled, calculation records shall distinguish the amount of the raw material compound, the conversion factor for the ascorbic acid moiety, purity, moisture content, and the proportion contained in the preparation. Where amounts of elements derived from salts are also stated, their calculation and the calculation of the vitamin C amount shall be verified independently. Mass units and amounts of raw material preparations shall not be confused.
- 3. For dissolution, granulation, drying, tableting, filling, and other processes, dissolved oxygen, contact metals, pH, heating, illumination, and holding time shall be controlled in relation to oxidation risks. In combination formulations containing iron or copper, contact conditions shall be evaluated, and remaining amounts before and after process changes shall be compared. The amount added alone shall not serve as the basis for final product specifications.
- 4. The quantitative method shall distinguish the effects of reduced ascorbic acid, oxidized components converted during analytical operations, and coexisting reducing substances. Where total vitamin C is measured, the scope of components subjected to reduction shall be stated in the procedure and the certificate of analysis; where only the reduced form is measured, that fact shall be stated. Third-party testing shall identify the sample lot, pretreatment, reference standards, forms measured, and conversion process.
- 5. Stability evaluation shall examine light, heat, oxygen, moisture, and the gas and light permeability of containers for each product dosage form. For liquid products, products used after dissolution, and products opened repeatedly, changes after opening or preparation shall be verified. The business operator shall establish specifications for the guaranteed amount at the end of shelf life and shall present them together with storage documentation for the actual product. Protection from light, tight closure, and other necessary handling instructions shall be stated on the label.
- 6. Content labeling shall express the vitamin C equivalent amount by mass corresponding to the recommended daily intake or a product unit and shall allow verification of the form used and whether conversion has been applied. Where the product is labeled as a food with nutrient function claims, documentation shall be used to verify that the labeled amount, recommended intake, nutrition labeling, prescribed nutrient function claim, and cautionary statement comply with the requirements of the applicable regulatory system at the time of application.
- 7. Intake labeling shall provide guidance on avoiding excessive intake, taking into account duplicate intake from other foods or supplements containing vitamin C. Instructions to discontinue use and seek consultation if adverse changes in physical condition occur following intake, and guidance on prior consultation for users undergoing treatment, taking medication, or otherwise requiring individual assessment, shall be provided according to the product specifications. The business operator shall establish specific intake amounts on a substantiated basis.
Article 5 (Evaluation Categories)
- Conformity: Chemical forms, equivalent amount conversions, oxidation control, product quantification, guarantees at the end of shelf life, and verification of regulatory labeling can be traced consistently.
- Partial conformity: Forms and product content can be verified, but supplementary information is needed on stability after preparation or the scope of measurement of oxidized components, and a plan for providing that information is recorded.
- Nonconformity: The amount of a raw material preparation is treated as the vitamin C amount, no conversion basis is presented, or labeling at the end of shelf life is supported solely by the amount added without evaluation of oxidation effects.
Article 6 (Implementation)
The business operator may issue a self-declaration of conformity on the basis of raw material specifications by form, conversion records, process oxidation control, product testing, and stability documentation. Upon application, the Council may verify traceability from the labeled amount to the product lot, raw material form, and analytical results. Reevaluation shall be conducted when the chemical form, formulation, pH, process, packaging, or analytical method is changed.
Supplementary Provisions
This Standard shall take effect on 6 September 2026.
※ This Standard sets out evaluation criteria for information disclosure and quality management practices and does not guarantee the efficacy or safety of individual products.