Vitamin K2: why is it taken with D3, and how much do you need?

Ingredient spotlight · Vitamin K2 in Health Royals’ Peak Performance, multivitamin for women with omega 3 · 7 min read

Vitamin D3 increases how much calcium the body absorbs, and vitamin K2 is needed by the proteins that bind that calcium into bone, which is why the two are usually taken together. Vitamin K contributes to the maintenance of normal bones. The reference intake is 75 µg, and Peak Performance Formula contains 90 µg of K2 as MenaQ7®, in the MK-7 form, alongside 25 µg of vitamin D3. If you take warfarin, ask your doctor first.

Vitamin C and vitamin D are familiar to most people. Vitamin K is less so, and it is often spoken about as though it were a single nutrient. In reality the name covers a family of related fat-soluble compounds. Vitamin K1 is the form found in leafy greens, while vitamin K2 is a group of forms called menaquinones. One of them is menaquinone 7, or MK-7.

Here we cover what MK-7 means, why K2 is taken with vitamin D3, what MenaQ7® is, and why Peak Performance, our daily multivitamin for women with omega 3 from algae, contains 90 µg.

Vitamin K2 at Health Royals

Peak Performance contains 90 µg of vitamin K2 per daily dose as MenaQ7®, in the menaquinone 7 form, MK-7, which is 120 per cent of the nutrient reference value, together with 25 µg of vitamin D3. Vitamin K contributes to the maintenance of normal bones. Vitamin D contributes to the maintenance of normal bones and to normal muscle function. If you take anticoagulant medication, talk to your doctor before using a supplement with vitamin K2.

See Peak Performance, multivitamin for women with omega 3

How is vitamin K2 different from K1?

Vitamin K1, also called phylloquinone, is found mainly in green vegetables such as kale, spinach, broccoli and Brussels sprouts.

Vitamin K2 is a family of menaquinones. They occur in certain fermented foods and foods of animal origin, although the amount and the specific form vary considerably.

Both contribute to the body's vitamin K functions. Vitamin K contributes to normal blood clotting and to the maintenance of normal bones.

The difference between the forms lies in their structure. K2 compounds have side chains of different lengths, which is why they carry names such as MK-4 and MK-7. Those differences affect how the compounds are transported and how long they stay available in the circulation. K1 and K2 belong to the same family, but they are not identical.

What does MK-7 mean?

MK stands for menaquinone, and the number is the number of repeating units in the side chain of the molecule. MK-7, menaquinone 7, is a long-chain form of vitamin K2.

Compared with vitamin K1 and the shorter MK-4, MK-7 stays in the circulation for longer. In a comparison of synthetic vitamin K1 and natto-derived menaquinone 7, published by Schurgers and colleagues in Blood in 2007, MK-7 remained in circulation considerably longer, which gives steadier levels with a regular daily intake. It is also one reason MK-7 is the form usually chosen for supplements in microgram amounts.

In a later study in the British Journal of Nutrition in 2012, Theuwissen and colleagues reported that low-dose menaquinone 7 supplementation improved vitamin K status outside the liver in healthy adults.

The form name does not tell the whole story. Purity, stability, isomer profile, manufacturing and the daily amount matter too. "Vitamin K2" names the family. "MK-7" names the form.

Why is vitamin K2 taken together with vitamin D3?

Because the two act on the same tissue from different sides.

Vitamin D contributes to the normal absorption and utilisation of calcium and phosphorus, and to the maintenance of normal bones. Vitamin K contributes to the maintenance of normal bones.

At a biochemical level, vitamin K works as a cofactor when certain vitamin K dependent proteins are activated, among them osteocalcin and matrix Gla protein, which are involved in bone mineralisation and the handling of calcium. Vitamin D supports the production of some of those proteins. Vitamin K is then needed to activate them, through a process called carboxylation.

That is the background to the pairing. The two do not do the same job, and one does not replace the other. In Peak Performance the vitamin D is 25 µg of D3 as Quali-D® from dsm-firmenich, and why we chose that dose is set out in our article on vitamin D3 and Quali-D®.

Why does bone become a bigger question from midlife?

Because the skeleton is living tissue that is broken down and rebuilt all through life, and the balance between the two shifts with age.

For women, bone often becomes more relevant from midlife onwards. When oestrogen falls around the menopause, bone turnover can change and the loss of bone mass can increase. We cover the wider picture in the biology of menopause.

That makes the everyday foundations more important: weight-bearing movement, strength training, enough protein, and a diet that provides calcium and vitamin D. Vitamin K is one part of that whole.

What is MenaQ7®, and who makes it?

MenaQ7® is a vitamin K2 raw material from Gnosis by Lesaffre. It is produced by fermentation and provides vitamin K2 in the all-trans MK-7 form, a clearly identified source rather than a generic vitamin K2.

We chose it for the same reasons we choose any raw material: a known form, a known manufacturer, documented quality and traceability. Two labels can look alike; the difference lies in the form and the documentation behind it. Health Royals works with specialist manufacturers, researchers and supplier networks when raw materials are chosen, as we explain in branded and non-branded ingredients.

Why does Peak Performance contain 90 µg of vitamin K2?

Because it is a nutritional amount set a little above the reference intake, to be taken every day alongside the vitamin D.

The EU nutrient reference value for vitamin K is 75 µg. 90 µg is 120 per cent of that. It is not presented as a studied dose, and we do not describe it as one. It is a nutritional level, chosen in the same spirit as the 25 µg of D3: above the reference intake, with no reason to go higher. For us, the dose matters as much as the raw material.

How does vitamin K2 fit into Peak Performance?

Vitamin K2 and vitamin D3 are fat soluble, and in Peak Performance they sit in an oil-based softgel with OMEGATEX® algal oil and 450 mg of extra virgin olive oil, a lipid setting for fat-soluble vitamins.

The daily dose starts from the nutrients where Swedish intakes more often fall short, as we set out in what Riksmaten shows, plus the omega 3 that multivitamins usually leave out:

• Vitamin K2, 90 µg, as MenaQ7®, and vitamin D3, 25 µg, as Quali-D®, 500 per cent of the reference intake.
• OMEGATEX® algal oil, 500 mg, providing 375 mg of omega 3, of which 300 mg DHA and 50 mg EPA.
• Hytolive® olive fruit extract, 150 mg, providing 15 mg of hydroxytyrosol, and Extramel® melon extract, 10 mg, both at the daily amounts used in their human studies.
• Folate, 200 µg, as Quatrefolic® 5-MTHF, vitamin B12, 10 µg, as MecobalActive®, thiamin 1.1 mg and niacin 16 mg.
• Zinc, 5 mg, as L-OptiZinc®, selenium, 27.5 µg, and chromium, 20 µg.

Peak Performance does not contain calcium, magnesium or iron. Calcium for bone comes from food, and vitamin D and K2 are the part we have chosen to supply. That is what we mean by fewer jars, more thought. The jar is amber glass with a scented core, made to stay out on the shelf, with refill pouches by subscription.

Important: Vitamin K can affect vitamin K antagonist medicines such as warfarin, so if you take anticoagulant medication, talk to your doctor before using a supplement with vitamin K2.

We have done the selection so that you do not have to. Peak Performance gives you 90 µg of vitamin K2 as MenaQ7® with 25 µg of vitamin D3 as Quali-D®, in one daily dose with omega 3 from algae, at amounts we publish and can explain. You can stop looking.

See Peak Performance, multivitamin for women with omega 3

Go deeper

• Guide: wellbeing from within
• D2 or D3: which form of vitamin D is best, and why we chose Quali-D®
• Vitamin D deficiency and the Swedish winter
• Is omega 3 from algae as good as fish oil?
• The biology of menopause
• Branded and non-branded ingredients
• Peak Performance, multivitamin for women with omega 3

Frequently asked questions

What is the difference between vitamin K1 and vitamin K2?
K1, phylloquinone, comes mainly from green vegetables. K2 is a family of menaquinones from certain fermented and animal foods. They differ in structure and in how long they stay in circulation.

Why are vitamin D3 and vitamin K2 taken together?
Because they act on bone from different sides. Vitamin D supports the production of certain vitamin K dependent proteins, and vitamin K is needed to activate them.

How much vitamin K2 does Peak Performance contain?
90 µg of vitamin K2 as MenaQ7® MK-7 per daily dose, 120 per cent of the reference intake, in the same softgel as 25 µg of vitamin D3.

Does Peak Performance contain calcium?
No. Peak Performance contains vitamin D3 and vitamin K2 but no calcium, magnesium or iron. Calcium comes from food such as dairy products, fortified plant drinks and green vegetables.

Can I take vitamin K2 if I use anticoagulant medication?
Vitamin K can affect vitamin K antagonist medicines such as warfarin. If you take anticoagulant medication, talk to your doctor before using a supplement with vitamin K2.

References

National Institutes of Health, Office of Dietary Supplements. Vitamin K: Fact Sheet for Health Professionals.

EFSA Panel on Dietetic Products, Nutrition and Allergies. Dietary Reference Values for vitamin K. EFSA Journal. 2017.

Schurgers, L.J.; et al. Vitamin K-containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7. Blood. 2007.

Theuwissen, E.; et al. Low-dose menaquinone-7 supplementation improved extra-hepatic vitamin K status in healthy adults. British Journal of Nutrition. 2012.

Mladěnka, P.; et al. Vitamin K: sources, physiological role, kinetics, deficiency, detection, therapeutic use, and toxicity. Nutrition Reviews. 2022.

Disclaimer: This article is intended for general information and educational purposes only and does not constitute medical advice. Individual needs may vary. If you are pregnant or breastfeeding, have a medical condition, take medication, particularly anticoagulant medication, or have questions about your personal health, consult a qualified healthcare professional before using supplements.