Vitamin K in leafy greens destabilises warfarin therapy (archive citing a Medicine (Baltimore) review).
Original statement
No Arabic original wording available.
Translation
Vitamin K in leafy greens destabilises warfarin therapy (archive citing a Medicine (Baltimore) review).
Origin
- Source status
- Archive editors
- Attribution
- Archive editors
- Origin
- https://eltayebat.com/rule/leafy-greens-cucurbits/
- Attribution uncertainty
- Archive editorial text and study selection written by the archive operators, not necessarily by Elawady.
- Claimed mechanism
Vitamin K antagonises vitamin K antagonists.
- Claimed health effect
Unstable INR.
- Population concerned
Patients on vitamin K antagonists
- Geographic restriction by Elawady
none found
Scientific assessment
Mostly false – Essential parts of the statement are not supported by the evidence or are strongly exaggerated.
Certainty of evidence: low – Further research is likely to change the assessment considerably.
1. What was claimed?
Greens destabilise warfarin therapy.
2. What is demonstrably correct?
Large changes in vitamin K intake can influence INR; very high intakes may have an effect.
3. What is wrong or exaggerated?
The cited review concluded that 'the available evidence does not support current advice to modify dietary habits when starting therapy with VKAs' and that restriction is not a valid strategy; it recommends stable intake.
4. What remains unclear?
Evidence base is small and heterogeneous.
5. Which studies support it?
None that supports avoidance.
6. Which studies contradict it?
Violi 2016.
7. What applies to Germany and Europe?
Phenprocoumon is the main vitamin K antagonist in Germany; similar principle applies.
8. What is known about Egypt?
Not specific.
9. What practical conclusion is appropriate?
Patients on vitamin K antagonists should keep greens intake stable rather than eliminate it, and should not change diet without informing their doctor.
Assessment details
- Rationale for certainty of evidence
The cited systematic review (2 interventional, 9 observational studies) found conflicting evidence, an effect possibly only above ~150 µg/day, and concluded that evidence does not support advising dietary modification; it recommends stable habits. The archive reverses the review's conclusion. Underlying studies are few and heterogeneous, hence low certainty.
- Source quality
Archive misrepresents the conclusion of its own source.
- Regional transferability
Applies to patients on warfarin/phenprocoumon in Germany and Egypt.
- Individual exceptions
Large sudden changes in vitamin K intake can affect INR; stable intake is advised.
- Regional scope of the claim
- not specified
- Last reviewed
- 25 October 2026 provisional
In plain language
The archive claims that the vitamin K in leafy greens disrupts blood-thinning treatment with warfarin. The review it cites concluded the opposite: the evidence does not support telling patients to avoid such foods, and keeping intake stable is what matters. Patients on these drugs should not make large sudden changes in their diet without medical advice.
Studies on this claim
Studies supporting the claim (0)
No studies in this group.
Studies contradicting or limiting the claim (1)
-
Vitamin K foods and warfarin
Violi F et al.. Medicine (Baltimore) 2016 · PMID 26962786 · DOI 10.1097/MD.0000000000002895Systematic reviewcited by the Tayebat archivefull text checked★ key studyReview found no good evidence that patients on warfarin should restrict leafy greens; stable intake matters.
Does the study support the specific claim? No · Methodological quality: low · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Assess diet-warfarin interaction
- How was the study done?
Systematic review
- How many people, animals or samples were studied?
11 studies
- What was actually found?
Conflicting; no basis for restriction
- How large was the observed effect?
Effect possibly >150 µg/day
- What do the results mean in everyday life?
Keep intake stable.
- What are the study's limitations?
Few studies
- What does it say about Elawady's specific claim?
Contradicts archive
- Do the results apply to Germany and Europe?
High
- What can explicitly not be concluded from this study?
Cannot show greens must be avoided.
No study in this group is marked as key.
Studies with mixed or unclear results (0)
No studies in this group.
Regional context
Germany / EU
Phenprocoumon is the main vitamin K antagonist in Germany; similar principle applies.
Egypt
Not specific.
What applies in my country?
General scientific assessment
Mostly false The archive reverses the conclusion of its own source; stable intake, not avoidance, is advised.
The following areas of food safety are relevant to this statement:
- Pesticides and pesticide residues
- Contaminants (heavy metals, PFAS, PCBs, dioxins, nitrate)
- Pathogens (Salmonella, Campylobacter, etc.)
Fruit and vegetables
Choose a country to see the checked information for it.
Limits: legal rules describe what is allowed, not what every single food contains. Measurement data come from samples and are meaningful only together with their method details.
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References
- Interaction Between Dietary Vitamin K Intake and Anticoagulation by Vitamin K Antagonists: Is It Really True?: A Systematic Review.. Violi F et al.. Medicine (Baltimore) 2016 · PMID 26962786 · DOI 10.1097/MD.0000000000002895