NutriStack
Methotrexate (Cancer) and Methylfolate, contraindicated.
Folate can interfere with methotrexate's anticancer mechanism. Note: folate supplementation IS beneficial with low-dose MTX for rheumatoid arthritis.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
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What the row says.
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At a glance
- Substances
- Methotrexate (Cancer) and Methylfolate
- Pair type
- Contraindicated
- Evidence (highest tier)
- Strong
- Source citations
- 1 source
- Stack Score effect
- −25 to your Stack Score (per scored contraindication row).
- Scope
- Supplement × Supplement
- Last verified
- May 30, 2026
Contraindicated · Strong evidence
Contraindicated
What is happening. Folate can interfere with methotrexate's anticancer mechanism. Note: folate supplementation IS beneficial with low-dose MTX for rheumatoid arthritis.
Mechanism. Folate bypasses MTX's dihydrofolate reductase blockade, reducing anticancer efficacy.
Recommendation. Cancer patients on MTX should NOT take folate without oncologist approval.
Sources (1)
- Folate supplementation and methotrexate in RA PMID 14963199
Stack Score
How this pair moves the number.
Effect on the composite score
If both Methotrexate (Cancer) and Methylfolate are in the same stack, this pair applies −25 to your Stack Score (per scored contraindication row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
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