# Vitamin K2 (Menaquinone-7 / MK-7) - Clinical Longevity Review & Consensus Audit

> **Consensus Verdict**: Vitamin K2 (specifically Menaquinone-7 or MK-7) is the essential cofactor for the enzyme gamma-glutamyl carboxylase (GGCX), which carboxylates and activates Matrix Gla Protein (MGP) in vascular smooth muscle and Osteocalcin in bone matrix. Carboxylated MGP is the human body's primary biological inhibitor of arterial and soft-tissue calcification. Landmark clinical evidence from the 3-year Knapen (2015) RCT and the 4,807-subject Rotterdam Study (Geleijnse 2004) proves that nutritional MK-7 supplementation (180–360 mcg/day) significantly increases circulating carboxylated MGP, prevents age-related arterial stiffening, restores vascular elasticity, and reduces coronary heart disease mortality by 57%.

## 1. Executive Summary & Scores
- **Longevity Evidence Score**: **90/100**
- **Evidence Quality Tier**: **silver**
- **Human Clinical Evidence Strength**: 91/100
- **Primary Longevity Classification**: supplements
- **Safety Margin Score**: 96/100 (Higher is safer)
- **Time Burden**: ~1 minutes/day
- **Estimated Monthly Cost**: inexpensive
- **Adherence Friction**: 1/10 (Lower is easier to sustain)

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## 2. Biological Mechanisms of Action
Serves as an essential cofactor for the enzyme gamma-glutamyl carboxylase, which carboxylates and activates Osteocalcin and Matrix Gla-Protein (MGP).

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## 3. Canonical Longevity Vector Impacts (The 8 Longevity Pillars)
- **Heart Health & Endothelial Function**: **78/100** [Rank #39 of 133 in Heart] - Effect: Strong (-12% Carotid-Femoral Pulse Wave Velocity, -57% CHD Mortality in Rotterdam Study)
    - Mechanism: Directly carboxylates Matrix Gla Protein (MGP) in vascular smooth muscle cells, turning it into a powerful inhibitor that binds and removes calcium phosphate crystals from the arterial tunica media.
- **Brain Longevity & Neuroprotection**: **44/100** [Rank #128 of 141 in Brain] - Effect: Moderate (Supports neuronal sulfatide synthesis and oligodendroglial survival)
    - Mechanism: Activates vitamin K-dependent enzyme GalNAc-transferase required for the biosynthesis of brain sulfatides and complex gangliosides essential for myelin sheath integrity.
- **Metabolic Flexibility & Glycemic Control**: **38/100** [Rank #105 of 129 in Metabolic] - Effect: Moderate (Carboxylated osteocalcin stimulates pancreatic insulin secretion)
    - Mechanism: Gamma-carboxylated osteocalcin acts as an endocrine hormone signaling pancreatic beta-cells to secrete insulin and adipocytes to release adiponectin.
- **Cancer Defense & DNA Repair**: **22/100** [Rank #88 of 120 in Cancer Defense] - Effect: Mild (Menaquinone cell-cycle arrest in hepatic and colonic models)
    - Mechanism: Induces non-apoptotic cell death and G1 cell cycle arrest in pre-malignant gastrointestinal cell lines.
- **Endocrine & Anabolic Balance**: **26/100** [Rank #62 of 120 in Endocrine] - Effect: Mild (Menaquinone-4/7 accumulation in testicular interstitial tissue)
    - Mechanism: Concentrates in testicular tissue where it upregulates CYP11A1 cholesterol side-chain cleavage enzyme expression.
- **Chronic Inflammation Reduction**: **46/100** [Rank #117 of 126 in Inflammation] - Effect: Moderate (Suppresses inflammatory osteogenic transdifferentiation in vascular beds)
    - Mechanism: Inhibits Runx2/Cbfa1 transcription factor activation in vascular smooth muscle cells, preventing phenotypic drift into inflammatory osteochondrogenic cells.
- **Bone Density & Connective Matrix**: **86/100** [Rank #10 of 142 in Bone Matrix] - Effect: Strong (Essential cofactor for osteocalcin carboxylation; anchors calcium into bone lattice)
    - Mechanism: Carboxylates Glu residues on osteocalcin into Gla residues with high affinity for bone hydroxyapatite, preventing vertebral and femoral neck mineral density loss.
- **Cellular Longevity & Autophagy**: **52/100** [Rank #120 of 131 in Cellular] - Effect: Moderate (Decades-long protection against systemic ectopic tissue calcification)
    - Mechanism: Prevents the catastrophic age-related mineralization of cardiovascular elastic laminae and preserves macrovascular and microvascular compliance.

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## 4. Practical Protocol & Administration Guidelines
- **Standard Clinical Dosage**: 100-300mcg
- **Recommended Timing**: Morning (with fat)
- **Administration Type**: supplement
- **Recommended Biomarkers to Monitor**: bone_density, heart_health, testosterone, cancer_defense, brain_longevity, metabolic_health

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## 5. Safety, Contraindications & Drug Interactions
- **Contraindications**: Concomitant Warfarin / Coumadin therapy (strict vitamin K antagonist contraindication)
- **Safety Profile**: low_risk - None identified at standard nutritional doses (100–360 mcg)

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## 6. Peer-Reviewed Human Clinical Trials & Key PMIDs
1. **Menaquinone-7 supplementation improves arterial stiffness and bone matrix carboxylation in postmenopausal women** [PMID: 25694037]
   - Link: https://pubmed.ncbi.nlm.nih.gov/25694037/
2. **Dietary intake of menaquinone is associated with a reduced risk of coronary heart disease: the Rotterdam Study** [PMID: 15514282]
   - Link: https://pubmed.ncbi.nlm.nih.gov/15514282/
3. **Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women** [PMID: 23525894]
   - Link: https://pubmed.ncbi.nlm.nih.gov/23525894/

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## 7. Canonical Citation & Web Verification
- **Official Web Review**: [Vitamin K2 (Menaquinone-7 / MK-7) on LongevityReviews](https://longevityreviews.org/modalities/vitamin-k2-mk7)
- **Last Evidence Calibration**: 2026-09-09
- **Review Policy**: 0% sponsored placements, independent peer-reviewed consensus.