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Vitamin K2

Vitamin3 forms compared ↓

Also known as: Menaquinone-7, MK-7, Vitamin K2 (MK-7), natto-derived K2, K2

A
Grade A
💊 45–180 mcg daily🎯 12 primary uses🔗 3 synergiesℹ️ Check contraindications

Overview

Vitamin K2 (MK-7) is a long-chain menaquinone that activates bone and vascular proteins involved in calcium regulation, supporting bone mineralization and cardiovascular health. MK-7 from plant sources like chickpea offers improved bioavailability and longer tissue half-life compared to K1.

Primary Uses
Bone densityCardiovascular healthCalcium metabolismDental healthBone healthBrain healthHormone supportBone health and mineralizationArterial calcification preventionOsteocalcin activationVascular calcification preventionArterial elasticity support

Compare Forms

3 forms

Different chemical forms vary in absorption, side effects, and best use cases. Higher bioavailability scores indicate better absorption.

MK-7 (Menaquinone-7)

HIGH 100

Long-chain K2 from natto, half-life ~3 days

Best for:Daily supplementationBone densityArterial calcification prevention

💡 Excellent. Sustained blood levels with once-daily dosing.

✅ Pros
  • • Convenient daily dose
  • • Best vascular evidence
  • • Synergistic with D3
⚠️ Cons
  • • More expensive than MK-4
  • • Warfarin interaction

📝 Default choice for K2 supplementation. 90-180 mcg/day typical.

MK-4 (Menatetrenone)

HIGH 85

Short-chain K2; rapidly cleared so needs multi-dose schedule

Best for:Osteoporosis (high-dose protocol)Specific clinical research

💡 Good but short half-life (~1 hour) requires 2-3 daily doses.

✅ Pros
  • • Bone-density trials at 45 mg/day
  • • Animal-source form
⚠️ Cons
  • • Inconvenient dosing schedule
  • • Therapeutic doses are very high

📝 Better data for high-dose bone protocols; otherwise MK-7 wins on convenience.

MK-7 + MK-4 Combination

HIGH 95

Both forms in one product

Best for:Comprehensive K2 coverageThose who can afford the premium

💡 Combined long + short half-life coverage.

✅ Pros
  • • Both isomers covered
  • • Hedge against form-specific differences
⚠️ Cons
  • • Most expensive option
  • • MK-4 portion still needs frequent dosing

📝 Nice-to-have but not necessary; MK-7 alone is well supported.

Dosage

Typical range
45–180 mcg daily
Timing
With meals containing dietary fat
With food
Essential—fat-soluble vitamin; absorption enhanced with dietary lipids
Dose Tiers
Moderate
90-180 mcg MK-7
Optimal
180-360 mcg MK-7
Therapeutic
45 mg MK-4
Upper Limit
No established UL
Duration

Bone mineralization benefits may require 6–12 months of consistent use; vascular benefits similarly require long-term intake

Special Populations

Pregnant and breastfeeding women should maintain adequate K2 intake (safe at typical supplemental doses). Caution in those on warfarin or other vitamin K antagonists—consult physician before supplementing.

Mechanism of Action

  • • Activates osteocalcin (bone mineralization protein)
  • • Activates matrix Gla protein (vascular health)
  • • γ-carboxylation of vitamin K-dependent proteins
  • • Directs calcium to bone, away from soft tissues

Evidence Quality

Evidence Grade A

Strong RCT and observational evidence, particularly for bone density and fracture risk reduction; good evidence for vascular calcification prevention. MK-7 form shows superior bioavailability and half-life (2.5 days) compared to MK-4 or vitamin K1. EPIC-Norfolk and other large cohort studies support cardiovascular benefits.

Safety & Contraindications

Contraindications
  • • Warfarin and other vitamin K antagonists—high-dose supplementation may reduce drug efficacy; consistent intake is preferred over variable intake

Interactions

💊 Medications
  • • Warfarin and other coumarin anticoagulants—may reduce anticoagulant effect; consistency is key
  • • Some antibiotics (broad-spectrum) may reduce K2 production by gut bacteria
🧪 Supplements
  • • Synergistic with vitamin D and calcium for bone health
  • • May complement magnesium and boron for optimal bone metabolism

Stacking & Synergies

Pairs Well With
Vitamin D3CalciumMagnesium
Avoid Combining With
Warfarin without monitoring
Best Goal Synergies
Bone healthHeart health

Buying Guide

Standardization Markers
MK-7 content should be verified; bioavailability studies confirm natto-derived MK-7 is effective
Practical Notes
  • • Always pair with D3
  • • Critical for high-dose D3 users
  • • Requires 3x daily dosing
  • • May combine with MK-7
Tags
fat-solublebone healthheart healthbrain healthcardiovascular healthvitaminbone mineralizationvegan-sourcedplant-basedlong-chain menaquinonehigh-bioavailabilitybone-healthcardiovascularfat-soluble-vitamin

Frequently Asked About Vitamin K2

How much Vitamin K2 should I take?
The typical effective range is 180-360 mcg MK-7. Individual needs vary based on age, body weight, diet, and goals — start at the lower end and adjust based on response. Always consult a healthcare provider before starting a new supplement.
When is the best time to take Vitamin K2?
With meals containing dietary fat. Consistency matters more than perfect timing — pick a daily anchor (e.g. with breakfast or before bed) and stick with it.
Should I take Vitamin K2 with food?
Essential—fat-soluble vitamin; absorption enhanced with dietary lipids.
What is the best form of Vitamin K2?
MK-7 (Menaquinone-7) is generally the best-absorbed form (Long-chain K2 from natto, half-life ~3 days). Cheaper forms exist but often deliver less usable Vitamin K2 per dose.
Does Vitamin K2 interact with medications?
Yes — known interactions include Warfarin and other coumarin anticoagulants—may reduce anticoagulant effect; consistency is key and Some antibiotics (broad-spectrum) may reduce K2 production by gut bacteria. If you take any prescription medication, talk to your doctor or pharmacist before starting Vitamin K2.
What does Vitamin K2 pair well with?
Vitamin K2 stacks well with Vitamin D3, Calcium, and Magnesium — these combinations either improve absorption or work synergistically toward common goals.
Who should not take Vitamin K2?
Vitamin K2 should be avoided or used with caution by people with Warfarin and other vitamin K antagonists—high-dose supplementation may reduce drug efficacy; consistent intake is preferred over variable intake. Pregnant or breastfeeding women should consult a healthcare provider before use.

Top Products with Vitamin K2

Highest-scored catalog products containing Vitamin K2, ranked by our scoring engine.

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Related Guides

In-depth guides covering Vitamin K2 — protocols, comparisons, and use cases.

Educational content based on published research and our scoring methodology. Not medical advice — consult a qualified healthcare provider before starting, stopping, or changing supplements, especially if you take medications, are pregnant, or have a medical condition.