What the permitted-forms rule covers
Under the food supplements Directive 2002/46/EC, a supplement may contain only the vitamins and minerals in Annex I. Each must come from a substance listed in Annex II. A salt, ester or derivative missing from Annex II cannot be used as a vitamin or mineral source in a supplement sold in the EU. The Directive also fixes the labelling units, which is why the “vitamin D IU to mcg” question arises: EU labels declare vitamin D in µg, not IU.
The rule applies to every food business operator placing a food supplement on the EU market. That includes importers and brand owners who use contract manufacturers. It concerns the source substance, not the format: capsules, tablets, powders and gummies are treated alike.
Annex I and Annex II: what each list does
Annex I is the list of nutrients. It names the vitamins and minerals a supplement may contain and the unit in which each is declared.
Annex II is the list of substances. Under each nutrient heading, it names the compounds that may supply that vitamin or mineral. For vitamin D it lists cholecalciferol and ergocalciferol. Among the mineral sources it lists magnesium oxide and calcium carbonate.
Annex II has been amended several times since 2002. Work from the consolidated version on EUR-Lex, not the original text or a secondary list.
Several other acts bear on which form you can use and how:
| Act | Scope | Relevance to vitamin and mineral forms |
|---|---|---|
| Directive 2002/46/EC | Food supplements | Annex I nutrients, Annex II source substances, labelling units |
| Regulation (EC) No 1925/2006 | Addition of vitamins and minerals to ordinary foods | Separate lists for fortified foods |
| Regulation (EU) 2015/2283 | Novel foods | Sources new to the EU market or made by new processes |
| Regulation (EC) No 1333/2008 | Food additives | Use of the same substance for a technological function |
| Regulation (EU) No 231/2012 | Additive specifications | Purity criteria for substances that are also additives |
| Regulation (EU) No 1169/2011 | Food information to consumers | General labelling and reference intakes |
How to check whether a form is permitted
- Establish the exact identity of the material: chemical name, CAS number and formula from the specification sheet.
- Open the consolidated Directive 2002/46/EC on EUR-Lex and go to the Annex II heading for the nutrient.
- Match the substance by name. The listing of one salt does not cover a different salt or a related compound.
- If the substance is not listed, stop. Using it requires an amendment to Annex II, and possibly novel food authorisation as well.
- Check the purity criteria that apply to the substance.
- Check the national rules of each member state where the product will be sold.
SoleChem’s specification sheet identifies each material by name and CAS number, so it can be matched against the Annex II entry. Ask for it in the quote form.
Where the novel food regulation applies
Regulation (EU) 2015/2283 covers food not consumed to a significant degree in the EU before 15 May 1997. For vitamin and mineral sources it matters in two situations.
- A substance new to the EU market. It needs novel food authorisation before it can be sold.
- A listed substance made a new way. A production process not used before that date can bring a source into scope where it significantly changes composition or structure. Sources consisting of engineered nanomaterials are also in scope.
Authorised novel foods appear in the Union list in Implementing Regulation (EU) 2017/2470. Each entry carries specifications and, where appropriate, conditions of use. Novel food authorisation does not by itself add a substance to Annex II, so check both lists. The novel food status guide covers the procedure in more detail.
Purity criteria and specifications
The Directive also governs the purity of Annex II substances. Where Union law sets specifications for a substance used as a food additive, those specifications apply. Otherwise, generally accepted criteria recommended by international bodies apply until Union criteria are adopted.
In practice, many mineral salts and some vitamins are also authorised food additives. Their specifications are in Regulation (EU) No 231/2012. The certificate of analysis states which standards a lot conforms to.
The same substance can serve two purposes. Ascorbic acid can be a vitamin C source or an antioxidant. When it performs a technological function, Regulation (EC) No 1333/2008 governs that use.
Label units: vitamin D IU to mcg and vitamin E IU to mg
Annex I sets the declaration units. Vitamin D is declared in µg and vitamin E in mg alpha-tocopherol equivalents. Vitamin A is declared in µg retinol equivalents. International units are not the EU declaration unit for any of these vitamins.
Documents from outside the EU often express potency in IU, as do some older pharmacopoeial texts. Convert to the Annex I unit before the label is finalised.
For vitamin D, one fixed IU-to-µg factor applies to both cholecalciferol and ergocalciferol. Vitamin E is less simple. The factor depends on whether the form is natural (RRR) or synthetic (all-rac). It also depends on whether the material is free tocopherol or an ester such as the acetate or, in the natural form only, the acid succinate. Using the factor for one form on another gives a wrong declaration.
Two further points cause errors:
- The weight of a tocopheryl ester is not its weight in alpha-tocopherol equivalents.
- Diluted forms, such as vitamin D on a carrier, state potency per gram on the certificate of analysis. Calculate from that figure, not from the powder weight.
The vitamin unit converter applies the factors by form. Form-by-form detail is in the vitamin D forms and vitamin E forms guides. Declaration format and placement are covered in labelling a food supplement in the EU.
Fortified foods follow a separate list
Regulation (EC) No 1925/2006 governs vitamins and minerals added to ordinary foods. It has its own Annex I and Annex II. These overlap with the supplement lists but are not identical.
A form permitted in supplements is not automatically permitted in a fortified food, and the reverse also holds. Check the list for the product category you are making. This matters for borderline products, such as drink powders that may be classed as either.
What the annexes do not settle
- Maximum and minimum amounts. Article 5 of the Directive provides for EU maximum levels, but none have been adopted. Member states apply their own limits. See maximum levels by EU country.
- Other substances. Amino acids, botanical extracts and similar ingredients fall outside Annexes I and II. Apart from EU-wide rules such as Annex III of Regulation (EC) No 1925/2006 and the novel food regulation, national rules govern them and differ between member states.
- Claims. Nutrition and health claims fall under Regulation (EC) No 1924/2006. See the health claims guide.
- Notification. Member states may require notification, with a model of the label, when a supplement is placed on their market. Procedures differ by country.