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evidence · mechanism · dose
Supplements/Vitamin

Vitamin K1 (Phylloquinone)

Leafy-green K1 essential for hepatic coagulation factors.

Cardiovascular HealthBone HealthGeneral Wellness

Overview

Leafy-green K1 essential for hepatic coagulation factors.

Natural sources
    Common forms

      Mechanism of action

      Cofactor for γ-glutamyl carboxylase activating clotting factors II, VII, IX, X.

      Pathways

        Effects on the body

        Organ system effects

        Evidence-based benefits

        Required for normal coagulation

        Strong evidence

        Potential side effects

        Common
          Rare
            Serious
            • · Antagonizes warfarin

            Drug interactions

            Warfarin
            Keep K1 intake consistent.
            severe

            Supplement interactions

            Pairs well with

            None listed.

            Avoid combining with

            No specific avoidances listed.

            Dosing & bioavailability

            Typical dose
            90–120 mcg
            With food?
            With fat

            Where to buy

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            Thorne
            Practitioner-grade · NSF tested

            Scientific evidence (8)

            RCTAm J Clin Nutr · 2008

            Phylloquinone and bone in women

            Booth SL, et al.

            3-year DB-RCT in 452 older adults.

            Key findings

            No effect on BMD but reduced fracture markers.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin K1 (Phylloquinone) — Required for normal coagulation

            Live PubMed search

            Live results for "Vitamin K1 (Phylloquinone) Required for normal coagulation" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin K1 (Phylloquinone) and "Required for normal coagulation". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin K1 (Phylloquinone) — randomized controlled trial

            Live PubMed search

            Live results for "Vitamin K1 (Phylloquinone) randomized controlled trial" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin K1 (Phylloquinone) and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin K1 (Phylloquinone) — meta-analysis

            Live PubMed search

            Live results for "Vitamin K1 (Phylloquinone) meta-analysis" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin K1 (Phylloquinone) and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin K1 (Phylloquinone) — pharmacokinetics

            Live PubMed search

            Live results for "Vitamin K1 (Phylloquinone) pharmacokinetics" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin K1 (Phylloquinone) and "pharmacokinetics". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin K1 (Phylloquinone) — safety adverse events

            Live PubMed search

            Live results for "Vitamin K1 (Phylloquinone) safety adverse events" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin K1 (Phylloquinone) and "safety adverse events". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin K1 (Phylloquinone) — dose response

            Live PubMed search

            Live results for "Vitamin K1 (Phylloquinone) dose response" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin K1 (Phylloquinone) and "dose response". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewGoogle Scholar · 1970

            Google Scholar: Vitamin K1 (Phylloquinone) — clinical evidence

            Live Scholar search

            Cross-database citation index for Vitamin K1 (Phylloquinone) as it relates to "clinical evidence".

            Key findings

            Includes preprints, theses, and journal articles. Useful for tracking citation counts and follow-on work.

            Open study
            Educational use only. This profile is not medical advice. Consult a qualified healthcare professional before starting any supplement, especially if you take prescription medication or have a chronic condition.