Vitamin K2 MK-7 vs. MK-4: Forms, Stability and Formulation Tips

Vitamin K2 is one of the most requested vitamins in new supplement formulations, and buyers usually have to choose between two forms: menaquinone-7 (MK-7) and menaquinone-4 (MK-4). Both belong to the vitamin K2 family, but they differ in structure, raw material form, potency calculation and stability in the finished product. This guide explains the differences from a formulation and purchasing point of view and lists what to check in the specification before you order.

What MK-7 and MK-4 have in common – and where they differ

All menaquinones share the same 2-methyl-1,4-naphthoquinone ring. The number after “MK” describes the length of the side chain: MK-4 carries four isoprene units, MK-7 carries seven. This longer chain makes MK-7 more lipophilic, which has consequences for how the raw material is supplied and processed.

Raw material forms and how to calculate the dosage

Vitamin K2 is dosed in micrograms per serving, so it is almost never used in pure form. Instead, manufacturers work with diluted grades whose potency is stated in ppm (parts per million) or as a percentage:

• Stabilised powders: the vitamin is bound to a carrier and protected against light and oxygen. A grade with 2,000 ppm contains 2,000 µg vitamin K2 per gram of powder.
• Oil solutions: preferred for softgels and liquid products.
• Crystalline material: the concentrated form, mainly for MK-4, used where the formulator prepares their own dilution.

Example: for 100 µg vitamin K2 per tablet you need 50 mg of a 2,000 ppm powder (100 µg ÷ 2 µg per mg). Always calculate with the assay stated on the certificate of analysis of the actual batch and plan an overage according to your own stability data.

Stability in the formulation

Vitamin K2 is sensitive to light, oxygen and heat. In practice, formulators should also pay attention to the combination with alkaline mineral salts: unprotected MK-7 can lose potency in contact with substances such as calcium carbonate or magnesium oxide. For multi-mineral tablets, encapsulated or stabilised grades are therefore the usual choice.

• Store raw materials cool, dry and protected from light in the closed original packaging.
• Run stability tests with the final formulation, packaging and storage conditions.
• For tablets, choose excipients with care. Fillers such as microcrystalline cellulose and lubricants such as vegan magnesium stearate are standard in vitamin tablets.

Checklist: what to look for in the specification

• Form of vitamin K2 (MK-7 or MK-4) and CAS number
• Potency (ppm or %) and the analytical method used for the assay
• For MK-7: the stated all-trans content
• Carrier and other ingredients of the powder, relevant for allergen and vegan declarations
• Particle size and flowability for tablet and capsule production
• Shelf life, storage conditions and packaging
• Documents: specification, CoA, SDS and the statements you need for your labelling

Regulatory note

In the EU, the vitamin and mineral forms that may be used in food supplements are listed in Annex II of Directive 2002/46/EC, and some forms are also covered by the Novel Food rules. Please check that the selected vitamin K2 form is permitted for your product category and target market. Claims on finished products must comply with Regulation (EC) No 1924/2006.

Frequently asked questions

Can MK-7 and MK-4 be exchanged 1:1 in a formulation?

Not without checking. The forms differ in structure, raw material format and potency of the available grades, so the recipe, dosage calculation and stability data must be reviewed when switching.

What does 2,000 ppm mean for vitamin K2 powder?

2,000 ppm means 2,000 µg vitamin K2 per gram of powder, which is 0.2%. The exact value of each batch is stated on the certificate of analysis.

Which form is better for softgels?

For softgels, oil-based or oil-dispersible grades are usually easier to process than dry powders. Tell us your dosage form and we will suggest a suitable grade.

Vitamin K2 from biolla chemicals

biolla chemicals supplies vitamin K2 MK-7, vitamin K2 MK-4 and a stabilised vitamin K2 2,000 ppm powder, as well as vitamin K1 and the full range of vitamins to food supplement, food and pharmaceutical manufacturers across Europe. Specification, CoA, SDS and samples are available on request.

• Contact form
• Email: info@biolla.de
• Phone: +49 40 67 555 155