Vitamin K2: MK-4 vs MK-7 - Half-Life, Sources, Calcification

Vitamins and minerals

🧬 Vitamin K2: MK-4 vs MK-7 - Half-Life, Sources, Calcification

Two forms of vitamin K2 - let's look at the difference and which to choose for bones and vessels

Vitamin K2 (menaquinone) is important for bone and vessel health. In supplements there are two main forms: MK-4 and MK-7. They differ in duration of action and sources. The choice of form matters.

Vitamin K2 helps direct calcium into bones rather than vessels. This is a key role. Let's look at how MK-4 and MK-7 differ and which form is chosen more often.

Key idea: vitamin K2 helps "direct" calcium into bones and prevent its deposition in vessels. MK-7 acts longer and is more often used in supplements. MK-4 acts shorter but is also used.

🧬 What is vitamin K2

Vitamin K is a group of fat-soluble vitamins. K2 (menaquinone) is important for calcium regulation: it helps calcium get into bones and not deposit in vessels.

Role: vitamin K2 activates proteins that "direct" calcium into bones and protect vessels from calcification. This is the key to its benefit.
Related topic: vitamin K2 is often combined with vitamin D3. More on D3 - in the article about vitamin D3 and D2.

💊 MK-4 and MK-7

The two main forms of vitamin K2 in supplements.

FormDurationSource
MK-4 (menatetrenone)ShortSynthetic, from animal foods
MK-7 (menaquinone-7)LongFermented soy (natto)
Nuance: MK-7 acts longer and is more often used in supplements. MK-4 acts shorter and requires more frequent intake.

🦴 Calcium and bones

Vitamin K2 helps calcium integrate into bone tissue. This is important for bone health and osteoporosis prevention.

Mechanism: K2 activates osteocalcin - a protein that "holds" calcium in bones. A K2 deficiency may leave calcium in the blood or vessels.
Important: vitamin K2 works together with calcium and vitamin D3. The balance of these nutrients matters for bones.

🫀 Vessel calcification

One of the main functions of K2 is protecting vessels from calcification (calcium deposition in artery walls).

Mechanism: K2 activates the matrix GLA protein, which prevents calcium deposition in vessels. This is linked to cardiovascular protection.
Practice: that is why K2 is often recommended to those taking calcium or vitamin D supplements - so calcium goes to bones, not vessels.

🔬 Half-life

The forms of K2 differ in their duration of action in the body (half-life).

MK-7: the half-life is long (about a day), so taking it once a day is enough. It provides a stable level.
MK-4: the half-life is short (hours), so it requires more frequent intake to maintain the level.

🥗 Sources and norms

Vitamin K2 is found in some foods.

FoodK2 content
Natto (fermented soy)Very high (MK-7)
Chicken (dark meat)Moderate (MK-4)
Egg yolkLow
Fermented cheeseModerate
IndicatorValue
Guide (adults)90–120 mcg/day
In MK-7 supplementsUsually 100–200 mcg/day
Caution: vitamin K2 may interact with anticoagulants (warfarin). With such medications - a mandatory doctor's consultation.

💡 What matters

How to sensibly approach vitamin K2.

1

Assess the need

K2 matters when taking calcium/vitamin D, or with bone or vessel issues.

2

Consider medications

With anticoagulants - a doctor's consultation; K2 may affect their action.

3

Choose the form

MK-7 is more convenient (once a day); MK-4 - when frequent intake is needed.

4

Combine with D3 and calcium

The balance of D3, K2 and calcium matters for bones and vessels. More in the article on magnesium and forms.

Bottom line: vitamin K2 (especially MK-7) helps direct calcium into bones and protect vessels from calcification. MK-7 acts longer and is more convenient. Combining with D3 and calcium matters, as does caution with anticoagulants.
❓ Frequently asked questions
How does MK-7 differ from MK-4?

MK-7 acts longer (half-life about a day) and is more convenient. MK-4 is shorter and requires more frequent intake.

Which K2 form to choose?

For convenience, MK-7 is more often chosen (once a day). MK-4 is used when frequent intake is needed.

Why take K2 with calcium?

K2 helps calcium go into bones rather than deposit in vessels. This reduces the risk of calcification.

Is K2 good for vessels?

Yes, K2 activates proteins that prevent calcium deposition in vessels. This is linked to vessel protection.

How much K2 per day?

A guide is 90–120 mcg/day. In MK-7 supplements, usually 100–200 mcg/day. Check the exact dose with a doctor.

Which foods provide K2?

Most K2 (MK-7) is in natto. MK-4 is in chicken and eggs. Moderately in fermented cheese.

Can K2 be taken with vitamin D3?

Yes, this is a common combination. D3 increases calcium absorption, and K2 directs it into bones.

Is vitamin K2 safe?

At recommended doses usually safe. With anticoagulants (warfarin) - a mandatory doctor's consultation.

Does K2 help with osteoporosis?

K2 participates in bone mineralization and may support bone health. With osteoporosis - comprehensive treatment with a doctor.

Does everyone need K2?

Especially important when taking calcium/vitamin D, with calcification risk and bone issues. The decision is with a doctor.

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