Safety Profile
Known Safety Concerns
- Critical interaction with warfarin — alters INR unpredictably
- Patients on anticoagulants must not alter vitamin K intake without medical guidance
- Rare: hypersensitivity reactions to injectable forms
- May interfere with other anticoagulants (rivaroxaban, apixaban)
Contraindications
- Critical interaction with warfarin — alters INR unpredictably
- Patients on anticoagulants must not alter vitamin K intake without medical guidance
Interactions
Information not yet available for this ingredient profile.
Evidence and Scientific Findings
Ingredient Overview
Vitamin K1 is essential for blood coagulation. It is generally safe at supplement doses but has a critical interaction with warfarin (coumarin anticoagulants) — even modest changes in vitamin K intake can destabilise INR control. Patients on warfarin must maintain consistent vitamin K intake. No UL has been established as toxicity from oral vitamin K1 is extremely rare.
Biological and Chemical Classification
- Scientific Name
- Phylloquinone / Phytonadione
Mechanism of Action
Information not yet available for this ingredient profile.
Clinical Evidence of Effectiveness
Information not yet available for this ingredient profile.
Pharmacokinetics
Information not yet available for this ingredient profile.
Recommended Dosage
Information not yet available for this ingredient profile.
SETI — Scientific Evidence Transparency Index
Executive Summary — Ingredient Assessment
- 10 studies reviewed
- 0 high-quality studies (meta-analysis or RCT)
- Main clinical benefit observed: Vitamin
- Evidence consistency: High consistency across studies (100%)
- Critical interaction with warfarin — alters INR unpredictably
- Patients on anticoagulants must not alter vitamin K intake without medical guidance
- Rare: hypersensitivity reactions to injectable forms
- May interfere with other anticoagulants (rivaroxaban, apixaban)
The available scientific evidence for Vitamin K1 (Phylloquinone) indicates notable safety signals that warrant caution. Use should be considered carefully and monitored, particularly in sensitive populations or alongside other medications.
Total SETI Score
High risk| Evidence quality | 10/40 |
| Evidence consistency | 20/20 |
| Safety signals | 0/20 |
| Study recency | 10/10 |
| Evidence transparency | 10/10 |
Evidence Summary
- 10 studies reviewed
- 0 high-quality studies (meta-analysis or systematic review)
- 0 studies identified benefits or no safety concern (GREEN)
- 10 studies reported limited or advisory safety evidence (YELLOW)
Evidence Policy
Only peer-reviewed scientific literature indexed in PubMed or comparable databases is included in this evaluation. Commercial websites, blogs, and marketing materials are excluded. All references include direct traceable links to source documents.
Last updated: 23 მარ 2026, 15:03
Evidence Distribution
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Observational / other LOW evidence YELLOWDetermination of vitamin K1 (phylloquinone) and K2 (menaquinones 4-10) in a broad range of matrices by HPLC with electrochemical reduction and fluorescence… ↗Ru00f8d KE et al.. Determination of vitamin K1 (phylloquinone) and K2 (menaquinones 4-10) in a broad range of matrices by HPLC with electrochemical reduction and fluorescence detection.. Food Chem. 2026. PMID:41679215.PMID 41679215 ↗Journal Food ChemYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41679215/
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Observational / other LOW evidence YELLOWA novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quick and efficient quantification of five fat-soluble vitamins. ↗Li SW et al.. A novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quick and efficient quantification of five fat-soluble vitamins.. Clin Chim Acta. 2026. PMID:40967265.PMID 40967265 ↗Journal Clin Chim ActaYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/40967265/
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Observational / other LOW evidence YELLOWHighly Selective Electrochemical Detection of Vitamin K1 (Phylloquinone) in Simulated Blood Serum Using Bimetallic Cu/Ni-MOF Decorated CNT Composite on Nickel Foam. ↗Ravipati M et al.. Highly Selective Electrochemical Detection of Vitamin K1 (Phylloquinone) in Simulated Blood Serum Using Bimetallic Cu/Ni-MOF Decorated CNT Composite on Nickel Foam.. ACS Appl Bio Mater. 2025. PMID:40514770.PMID 40514770 ↗Journal ACS Appl Bio MaterYear 2025Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/40514770/
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Observational / other LOW evidence YELLOWVitamin K2 Attenuates Mitochondrial Damage in Renal Proximal Tubular Cells. ↗Ho H et al.. Vitamin K2 Attenuates Mitochondrial Damage in Renal Proximal Tubular Cells.. J Agric Food Chem. 2025. PMID:40400071.PMID 40400071 ↗Journal J Agric Food ChemYear 2025Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/40400071/
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Observational / other LOW evidence YELLOWVitamin K - content in food and dietary intake among the Danes. ↗Jensen MB et al.. Vitamin K - content in food and dietary intake among the Danes.. Food Chem. 2025. PMID:39514936.PMID 39514936 ↗Journal Food ChemYear 2025Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/39514936/
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Observational / other LOW evidence YELLOWVitamin K content of Australian-grown horticultural commodities. ↗Dunlop E et al.. Vitamin K content of Australian-grown horticultural commodities.. Food Chem. 2024. PMID:38705117.PMID 38705117 ↗Journal Food ChemYear 2024Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/38705117/
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Observational / other LOW evidence YELLOWObservation of the neuroprotective efficacy of vitamin K in a streptozocin-induced diabetes model in chick embryos. ↗Vurmaz A et al.. Observation of the neuroprotective efficacy of vitamin K in a streptozocin-induced diabetes model in chick embryos.. J Biochem Mol Toxicol. 2024. PMID:38037266.PMID 38037266 ↗Journal J Biochem Mol ToxicolYear 2024Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/38037266/
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Observational / other LOW evidence YELLOWValidation of bioanalytical method for quantification of Vitamin K2 (MK-4) in human plasma by high-performance liquid chromatography-ultraviolet. ↗Putriana NA et al.. Validation of bioanalytical method for quantification of Vitamin K2 (MK-4) in human plasma by high-performance liquid chromatography-ultraviolet.. J Adv Pharm Technol Res. 2023. PMID:38107456.PMID 38107456 ↗Journal J Adv Pharm Technol ResYear 2023Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/38107456/
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Observational / other LOW evidence YELLOWMolecular Pathways and Roles for Vitamin K2-7 as a Health-Beneficial Nutraceutical: Challenges and Opportunities. ↗Jadhav N et al.. Molecular Pathways and Roles for Vitamin K2-7 as a Health-Beneficial Nutraceutical: Challenges and Opportunities.. Front Pharmacol. 2022. PMID:35774605.PMID 35774605 ↗Journal Front PharmacolYear 2022Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/35774605/
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Observational / other LOW evidence YELLOWCarboxylative efficacy of trans and cis MK7 and comparison with other vitamin K isomers. ↗Cirilli I et al.. Carboxylative efficacy of trans and cis MK7 and comparison with other vitamin K isomers.. Biofactors. 2022. PMID:35583412.PMID 35583412 ↗Journal BiofactorsYear 2022Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/35583412/
Score Transparency
0 of 10 approved references (score saturates at 10). More peer-reviewed studies = stronger evidence base.
Method: Q = number of approved references ÷ 10 (capped at 1.0)
Limited — mostly case reports or animal studies
Method: L = mean study-level weight across approved references. Level 1 (meta-analysis / systematic review) = 1.0; Level 2 (RCT) = 0.8; Level 3 (cohort/case-control) = 0.6; Level 4 (case report) = 0.4; Level 5 (animal / in-vitro) = 0.2.
Mixed or neutral — roughly equal benefit and risk signals
Method: D = (sum of risk-scored references − sum of benefit-scored references) ÷ total evidence score, then scaled from [−1, 1] to [0, 1]. 0.0 = pure benefit; 0.5 = neutral; 1.0 = pure risk.
One or more monitoring-level safety signals active
Method: S = 0.5 (neutral baseline) + sum of active signal severity deltas ÷ 10. Severity deltas: Critical = +2.0, High = +1.5, Moderate = +1.0, Low = +0.5. Capped at 1.0.
Final GIRI Score for Vitamin K1 (Phylloquinone). Risk level thresholds: Low 0–3.0 · Moderate 3.0–5.5 · High 5.5–7.5 · Critical 7.5–10.
Full methodology & data sources
The GIRI Score is computed entirely from structured data — no editorial scoring or subjective weighting is applied at any step.
- References: Only approved references are counted. Each reference is assigned an evidence level (L1–L5) and a direction (risk / neutral / benefit) by the reference manager or AI classifier.
- Safety Signals: Sourced from regulatory agencies (FDA, EMA, Health Canada, TGA, and others) and pharmacovigilance databases. Only active signals count toward the score.
- Formula version: GIRI Score v3.7.0 — Q × L × D × S × 10.
- Limitations: The score reflects published evidence and recorded signals as of the last update date. It is not a clinical risk assessment and should not replace advice from a qualified healthcare professional.
Risk Level Classification
Based on available regulatory signals and scientific evidence, this ingredient presents a low safety concern under normal conditions of use.
0–3.0
3.0–5.5
5.5–7.5
7.5–10
The score pin shows exactly where this ingredient falls on the fixed risk scale.
What drove the Low classification for Vitamin K1 (Phylloquinone)
A score of 3.0 places this ingredient in the Low band. Thresholds: Low 0–3.0 · Moderate 3.0–5.5 · High 5.5–7.5 · Critical 7.5–10.
0 approved references.
Limited — mostly case reports or animal studies (Level 4–5).
Neutral or mixed — benefit and risk signals roughly balanced.
No active signals — S component is at neutral baseline (0.5), contributing no extra risk weight.
No major regulatory restrictions or advisories recorded across monitored jurisdictions (FDA, EMA, Health Canada, TGA, and others).
How are the Low / Moderate / High / Critical thresholds defined?
The four risk levels are fixed score bands. A score is assigned to exactly one level based on where it falls:
| Level | Score | Meaning |
|---|---|---|
| LOW | 0.0 – 2.9 | Sparse or predominantly beneficial evidence. No active safety alerts. |
| MODERATE | 3.0 – 5.4 | Mixed signals — some risk alongside benefit. Caution at high doses or in sensitive groups. |
| HIGH | 5.5 – 7.4 | Multiple studies or regulatory alerts documenting adverse effects. Professional oversight recommended. |
| CRITICAL | 7.5 – 10 | Regulatory restrictions in one or more major jurisdictions. Serious documented harm. Avoid without specialist supervision. |
Thresholds are fixed constants (GIRI_Score_Utils::LEVEL_THRESHOLDS). They do not change per ingredient and are never subject to editorial adjustment.