Vitamin K1

Effects and Benefits

Core Identification

Common Names:
- Vitamin K1
- Phylloquinone
- Phytonadione

Latin Name: N/A (synthetic/isolated nutrient)

Category: Vitamin

Uses

Traditional Uses

• Treatment of bleeding disorders - Medical practice since 1930s
• Newborn hemorrhagic disease prevention - Standard medical protocol
• Counteracting anticoagulant overdose - Clinical medicine

Modern Uses

• Blood Clotting Support - Essential for normal coagulation | Research quality: Strong
• Key findings: Acts as a co-factor for production of clotting proteins II, VII, IX, X, protein C and protein S in the liver

• Source citations: Merck Manual Home Health Handbook; Brewer - Encyclopedia of Vitamins

• Bone Health - Supports bone density and reduces fracture risk | Research quality: Moderate

• Key findings: Needed for synthesis of osteocalcin (calcium-binding protein in bone matrix); studies suggest supplements can reduce loss of bone calcium in post-menopausal women by up to 50%; women getting at least 110 mcg daily are 30% less likely to break a hip

• Source citations: Brewer - Encyclopedia of Vitamins; Stewart - Living the Good Long Life; Nurses' Health Study

• Cardiovascular Health - May inhibit arterial calcification | Research quality: Moderate

• Key findings: Strong evidence from observational and clinical studies that suboptimal vitamin K levels play an important role in vascular calcification, especially for patients with chronic kidney disease
• Source citations: Advanced Nutrition (2012); Moline - Doctors Book of Natural Health Remedies; de la Forêt - Alchemy of Herbs

Active Compounds

Primary Active Ingredients:
- Phylloquinone - The plant-derived form of vitamin K; fat-soluble; acts as co-factor for gamma-glutamyl carboxylase enzyme needed to activate clotting factors and bone proteins

Dosage Information

Standard Dosage:
- Form: Tablet, capsule, or soft gel
- Amount: 90-120 mcg per day (general recommendation)
- Frequency: Once daily with a meal containing fat

Therapeutic Dosage:
- Form: Tablet or capsule
- Amount: 150-300 mcg per day
- Purpose: For bone health support or individuals with higher needs
- Duration: Ongoing with periodic assessment

Maximum Safe Dosage:
- Daily maximum: No established upper limit for K1 from food or supplements
- Warning threshold: The natural forms K1 and K2 appear to be completely safe at typical supplemental doses

Bioavailability Notes:
- Fat-soluble vitamin requiring dietary fat for optimal absorption
- Absorbed in the small intestine via lipid transport mechanisms
- Best taken with meals containing some fat
- Absorption can be impaired by conditions affecting fat digestion (e.g., bile duct obstruction, pancreatic insufficiency)

How to Take It

Timing:
- With meals for optimal absorption
- Take with food containing fat (oils, dairy, meat)
- Consistent daily timing recommended, especially for those on anticoagulant therapy

Synergies - What It Works Well With

Complementary Supplements:
1. Vitamin D - Both support bone health; work synergistically in calcium metabolism and bone mineralization
2. Calcium - Vitamin K1 helps direct calcium to bones via osteocalcin activation
3. Vitamin K2 - Complements K1; K2 provides additional cardiovascular and bone benefits through different tissue distribution

Avoidance - What NOT to Combine With

Supplement Interactions:
1. High-dose Vitamin E - Very high doses of vitamin E (over 1000 IU) may theoretically interfere with vitamin K activity, though clinical significance is debated

Drug Interactions:
1. Warfarin (Coumadin) - Vitamin K directly reverses anticoagulant effect; avoid supplements and maintain consistent dietary intake | Severity: Severe
2. Other Anticoagulants - May reduce effectiveness of blood thinners that work via vitamin K pathway | Severity: Moderate to Severe
3. Antibiotics (broad-spectrum) - Prolonged use can reduce vitamin K production by gut bacteria and may increase K1 needs | Severity: Moderate
4. Anticonvulsants - Some may interfere with vitamin K metabolism | Severity: Moderate
5. Orlistat (weight loss drug) - May reduce absorption of fat-soluble vitamins including K1 | Severity: Mild to Moderate
6. Mineral oil - Large amounts may reduce vitamin K absorption | Severity: Mild

Food Interactions:
- Very high-fat meals may enhance absorption but no foods need to be avoided
- Individuals on warfarin should maintain consistent intake of K-rich vegetables rather than avoiding them entirely

Safety Information

Contraindications:
- Individuals on warfarin or other vitamin K-dependent anticoagulant therapy should not supplement without medical supervision
- Those with a history of blood clots who are being managed with anticoagulants

Side Effects:
- No known toxicity from vitamin K1 at typical doses
- The natural forms K1 and K2 appear completely safe
- Note: The synthetic form vitamin K3 (menadione) can interfere with glutathione function and is not recommended

Long-Term Use:
- Considered safe for long-term use
- No established upper limit for K1
- Those on anticoagulant therapy require stable, consistent intake with medical monitoring

Special Precautions:
- Surgery: Inform surgeon of vitamin K supplement use due to potential effects on clotting
- Pregnancy: Safe at recommended amounts; essential for fetal development
- Newborns: Routinely given K1 injection at birth to prevent hemorrhagic disease; oral administration is an alternative
- Patients on anticoagulant therapy: Maintain consistent vitamin K intake; sudden changes in K-rich vegetable consumption can destabilize INR control

Primary Uses At-a-Glance

Primary: Blood clotting support, bone health, newborn hemorrhagic disease prevention

Secondary: Cardiovascular health (arterial calcification prevention), post-menopausal bone density support

Sources

Local Library:
- Brewer, Sarah - TDT Encyclopedia of Vitamins
- Merck - The Merck Manual Home Health Handbook
- Gaby, Alan R. - A-Z Guide to Drug-Herb-Vitamin Interactions 2nd Ed
- Moline, Peg - The Doctors Book of Natural Health Remedies
- Stewart, Martha - Living the Good Long Life
- de la Forêt, Rosalee - Alchemy of Herbs
- Moyad, Mark - The Supplement Handbook
- Weil, Andrew - Eating Well for Optimum Health
- WRCHM - Herb-Drug-Nutrient Interaction

General Knowledge:
- Nurses' Health Study (bone health research)
- Advanced Nutrition journal (2012 - cardiovascular research)
- Standard clinical and pharmacological references