Vitamin K1 (Phylloquinone)
Overview
Vitamin K1 (phylloquinone) is a fat-soluble vitamin found primarily in green leafy vegetables — spinach, kale, broccoli. It plays an essential role in blood clotting by activating liver-produced coagulation proteins. K1 is the main dietary form of vitamin K. Adults need 90–120 mcg daily. No upper limit has been established. Critical safety note: consistent vitamin K intake is essential for people on warfarin — sudden changes can significantly alter anticoagulant effectiveness.
Dosage
120 mcg · With meal · Take with food
Key Interactions
20 verified interactions found
Very high doses of Vitamin E (>800 IU/day) can interfere with Vitamin K-dependent coagulation factor carboxylation, potentially increasing bleeding risk. This is particularly relevant for those on anticoagulant therapy.
Avoid very high-dose Vitamin E supplementation (>400 IU/day) without monitoring. At normal doses, the interaction is not clinically significant.
View details →Optimal magnesium, vitamin K, and vitamin D intake prevents phosphate-driven vascular calcification and excessive parathyroid hormone elevation.
Vitamin K kann laut präklinischer Daten zusammen mit Prolin und Magnesium vaskuläre Verkalkung durch Phosphat entgegenwirken. Eine gemeinsame Einnahme ist unbedenklich.
View details →Vitamin K1 affects DNA stability through mechanisms that interact with selenium-dependent processes.
Vitamin K1 und Selen können laut präklinischer Daten gemeinsam Chromosomenstabilität beeinflussen. Eine gleichzeitige Einnahme ist unbedenklich.
View details →Vitamin K1 inhibits glucosamine incorporation into bacterial cell walls.
Menadion kann laut präklinischer Daten den Einbau von Glucosamin in Bakterienzellwände hemmen. Eine gleichzeitige Einnahme von Vitamin K1 und Glucosamin beim Menschen ist unbedenklich.
View details →Vitamin K3 binds to proteins containing tryptophan, changing their fluorescence properties.
Menadion kann laut präklinischer Daten bestimmte Tryptophan-Reste in Proteinen beeinflussen. Eine gleichzeitige Einnahme von Vitamin K1 und Tryptophan ist unbedenklich.
View details →Scientific Sources
- Source
- Source
- Bioavailable dietary phosphate, a mediator of cardiovascular disease, may be dec (2014)
- Vitamin K1 Increases Sister Chromatid Exchange in Vitro in Human Leukocytes and (1987)
- Macromolecular synthesis: effects of vitamin K and warfarin on macromolecular sy (1971)
- THE STRANGE CROSS-REACTION OF MENADIONE (VITAMIN K3) AND 2,4-DINITROPHENYL LIGAN (1974)
- NIH Dietary Supplement Label Database (DSLD)
- PubChem Compound 5284607
Frequently Asked Questions
What is Vitamin K1 (Phylloquinone) used for?
Vitamin K1 (phylloquinone) is a fat-soluble vitamin found primarily in green leafy vegetables — spinach, kale, broccoli.
What is the recommended dosage for Vitamin K1 (Phylloquinone)?
120 mcg. With meal. Take with food.
Does Vitamin K1 (Phylloquinone) interact with other supplements?
Vitamin K1 (Phylloquinone) has 20 verified interactions. Top: Vitamin E (Tocopherol), Proline.
When is the best time to take Vitamin K1 (Phylloquinone)?
With meal. Take with food.
Is Vitamin K1 (Phylloquinone) safe to combine with other supplements?
Always check interactions before combining supplements. Use VitalStack to verify your full stack for free.
Check how Vitamin K1 (Phylloquinone) fits your full stack
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Check Your Stack →Not medical advice. VitalStack is not a medical device. For personalized health recommendations, consult a healthcare provider.