VitalMatrix
VitaminsModerate

Vitamin K2

Also known as Menaquinone, MK-7

Vitamin K2 activates proteins (osteocalcin and matrix Gla protein) that bind calcium and deposit it in bone while keeping it out of arteries. It is the natural partner to vitamin D3, which increases calcium absorption but does not direct where it goes.

Bone healthCardiovascular health
By the Vital Matrix Editorial TeamReviewed by the Vital Matrix Research TeamLast updated June 25, 2026Moderate2 citations
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Benefits

Directs calcium to bone

Moderate

Activates osteocalcin, helping incorporate calcium into the bone matrix.

Arterial flexibility

Preliminary

Activates matrix Gla protein, which inhibits calcium build-up in arterial walls.

Pros & cons

Pros

  • Complements D3 and calcium perfectly
  • Excellent safety profile
  • MK-7 form has a long half-life (once-daily)

Cons

  • Evidence for hard outcomes is still developing
  • Interacts with blood thinners

Side effects

Very well tolerated

No established upper limit; side effects are rare.

Mild

How to take it

Typical dose

90–180 mcg per day (MK-7) or 45–90 mg per day (MK-4)

Timing

With a fat-containing meal, often alongside D3

Tip: MK-4 is taken at milligram doses (e.g. 45–90 mg) and clears quickly; MK-7 is taken at microgram doses (90–180 mcg) and lasts longer in the bloodstream.

Forms: which one to choose

The main forms of Vitamin K2 compared by absorption, tolerability, and best use.

MK-7 (Menaquinone-7)

Most popularHigh absorption

Best for: Bone and cardiovascular health, once-daily dosing · Long half-life (~72 h) and the most studied supplemental form

Read about MK-7 (Menaquinone-7)

MK-4 (Menaquinone-4)

High absorption

Best for: Bone health, high-dose protocols under clinician guidance · Short half-life (~1–2 h); requires divided dosing

Read about MK-4 (Menaquinone-4)

What the research says

  1. [1]Vitamin K2 and bone density

    Moderate

    Some trials report improved bone mineral density and reduced fracture markers, though results vary by population and dose.

    RCTs and reviews · 2017PubMed

  2. [2]Vitamin K2 and arterial calcification

    Preliminary

    A 2-year RCT of MK-7 plus vitamin D found no significant effect on arterial calcification progression; evidence for arterial benefits remains weak.

    Vascular health trials · 2022PubMed

How Vitamin K2 interacts

Synergies, absorption effects, and cautions between Vitamin K2 and other supplements in the matrix.

Vitamin K2 and its direct connections · click a node to open its guide

Synergy
Vitamin D3

D3 boosts calcium absorption; K2 ensures that calcium is deposited in bone, not arteries.

Compare the pairing
Synergy
Calcium

K2 activates the proteins that bind dietary calcium into the bone matrix.

Compare the pairing
Synergy
Boron

Boron and vitamin K2 both help direct calcium into bone for healthy mineralization.

Compare the pairing
See it on the matrix

Frequently asked questions

What is Vitamin K2 used for?

Vitamin K2 is most commonly used for bone health and cardiovascular health. Activates osteocalcin, helping incorporate calcium into the bone matrix.

How much Vitamin K2 should I take?

A typical dose is 90–180 mcg per day (MK-7) or 45–90 mg per day (MK-4). MK-4 is taken at milligram doses (e.g. 45–90 mg) and clears quickly; MK-7 is taken at microgram doses (90–180 mcg) and lasts longer in the bloodstream. Start at the lower end and confirm the right dose for you with a healthcare professional.

When is the best time to take Vitamin K2?

Recommended timing: With a fat-containing meal, often alongside D3.

What are the side effects of Vitamin K2?

Reported side effects include very well tolerated. No established upper limit; side effects are rare.

Who should be careful with Vitamin K2?

Can interfere with warfarin and other vitamin-K-antagonist anticoagulants; talk to your doctor. Speak with a healthcare professional if any of these apply to you.

Important cautions

  • Can interfere with warfarin and other vitamin-K-antagonist anticoagulants; talk to your doctor.

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Compare Vitamin K2 with

Weighing your options? See how Vitamin K2 stacks up against similar supplements.

Vitamin K2 vs Vitamin D3