Vitamin1 form

Vitamin K1

Evidence Level

Moderate Evidence

The Vitamin K1 form we carry

See how we score it — absorption, bioavailability & formulary tier

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Quick Answer

Which form of Vitamin K1 do we use?

Our formulary carries a single form of Vitamin K1. See the details below.

All Forms of Vitamin K1

Form	Tier	Form Score	Dose Range	Unit
Phylloquinone	Specialist	Verification pending	—	—

What is Vitamin K1?

Vitamin K1 is a Vitamin supplement available in 1 form.

FormulaForge carries a single form of Vitamin K1, so there is no form to choose here. Forms on the market do differ in how well they absorb, which is why it is worth checking the form named on any product label.

The Form of Vitamin K1 We Carry

Vitamin K1 (Secondary Form) has a bioavailability rating of good absorption.

What the Research Shows

Vitamin K1 (phylloquinone) is the primary dietary form of vitamin K, predominantly found in green leafy vegetables. It is the form most directly involved in hepatic synthesis of clotting factors. While MK-7 has superior extrahepatic activity, K1 remains clinically important for individuals on anticoagulant therapy requiring precise dosing management.

Human Phase-I PK: oral phylloquinone (vitamin K1) mixed-micelle pharmacokinetics; VKORC1-genotype dependent. PMID: 22864379

Human: supplemental phylloquinone (vitamin K1) bioavailability higher than from food (raw spinach). PMID: 10356087

How to Choose the Right Form

Multiple forms of Vitamin K1 are available. Start by comparing form ratings — Preferred Forms reflect the strongest bioavailability evidence, and higher-absorption forms deliver more active compound per dose unit.

The appropriate form depends on your individual goals and your healthcare provider’s recommendations. Consult a qualified professional before selecting a supplement form.

Dosing & Safety

Individual dose requirements vary based on health goals, body weight, and existing nutrient intake. Your healthcare provider can help you determine an appropriate amount of Vitamin K1 for you.

Side Effects: Consult your healthcare provider regarding tolerability, particularly at higher doses.

These statements are based on structure/function research and have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare provider before starting or changing a supplement regimen.

The Science

The following studies and findings inform FormulaForge classifications for Vitamin K1:

Human Phase-I PK: oral phylloquinone (vitamin K1) mixed-micelle pharmacokinetics; VKORC1-genotype dependent. PMID: 22864379

Human: supplemental phylloquinone (vitamin K1) bioavailability higher than from food (raw spinach). PMID: 10356087

Dosing Guidance

Individual dose requirements for Vitamin K1 vary based on health goals, body weight, and existing dietary intake. A qualified healthcare provider can help you determine an appropriate amount for you.

Frequently Asked Questions

Which form of Vitamin K1 is in our formulary?

Our formulary carries a single form of Vitamin K1. Focus on products that specify the form on the label — not all forms are equally absorbed by the body.

How much Vitamin K1 should I take?

Dosing for Vitamin K1 varies based on the specific form, your health goals, and individual factors. Consult a qualified healthcare provider for personalized guidance.

What does Vitamin K1 support?

Vitamin K1 is commonly used to support Vitamin. Research suggests it plays a role in several physiological pathways. As with all supplements, these statements have not been evaluated by the Food and Drug Administration and Vitamin K1 is not intended to diagnose, treat, cure, or prevent any disease.

Is Vitamin K1 safe?

Vitamin K1 is generally well-tolerated when taken at research-supported doses. As with any supplement, individual responses vary. Consult a qualified healthcare provider before use, especially if you are pregnant, nursing, have a medical condition, or take medications. These statements have not been evaluated by the Food and Drug Administration.

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References

Human Phase-I PK: oral phylloquinone (vitamin K1) mixed-micelle pharmacokinetics; VKORC1-genotype dependent. PubMed
Human: supplemental phylloquinone (vitamin K1) bioavailability higher than from food (raw spinach). PubMed

FormulaForge formulates and sells supplements containing the ingredients discussed on this page. Our formulary recommendations are based on peer-reviewed bioavailability research. All cited studies are independently verifiable.