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HEALTH

The Claim

Variants in the MTHFR gene are associated with increased inflammation in humans.

Verified by Lenz ·

The Short Version

The relationship between MTHFR variants and inflammation is real but far more nuanced than the claim suggests. Peer-reviewed evidence confirms that the C677T variant can associate with higher inflammatory markers (e.g., elevated NLR, CRP), but the other common variant—A1298C—trends in the opposite direction in the same study design. Treating "MTHFR variants" as a uniform class linked to increased inflammation overgeneralizes the evidence and omits variant-specific and population-specific differences that materially change the picture.

Caveats

  • The two most common MTHFR variants (C677T and A1298C) show opposite associations with inflammatory markers in direct comparisons, so the claim's blanket framing is misleading.
  • Many supporting associations come from disease-specific cohorts (e.g., multiple sclerosis patients) or are mediated through homocysteine, and may not generalize to baseline inflammation in healthy populations.
  • Several sources cited in support are commercial or supplement-marketing websites with financial conflicts of interest, not independent peer-reviewed research.

The Receipts

  1. Opposite impact of Methylene tetrahydrofolate reductase C677T and Methylene tetrahydrofolate reductase A1298C gene polymorphisms on systemic inflammation

    PMC

  2. Methylenetetrahydrofolate (MTHFR), the One-Carbon Cycle, and Cardiovascular Risks

    PMC

  3. Hyperhomocysteinemia is Associated with Inflammation, Bone Resorption, Vitamin B12 and Folate Deficiency and MTHFR C677T Polymorphism in Postmenopausal Women with Decreased Bone Mineral Density

    PMC

  4. MTHFR gene: MedlinePlus Genetics

    MedlinePlus Genetics

  5. Opposite impact of Methylene tetrahydrofolate reductase C677T and Methylene tetrahydrofolate reductase A1298C gene polymorphisms on systemic inflammation - PubMed

    PubMed

  6. Inflammatory profile, age of onset, and the MTHFR polymorphism in patients with multiple sclerosis

    PubMed

  7. Opposite impact of Methylene tetrahydrofolate reductase C677T and Methylene tetrahydrofolate reductase A1298C gene polymorphisms on systemic inflammation - PMC

    PMC

  8. Inflammatory profile, age of onset, and the MTHFR polymorphism in patients with multiple sclerosis - PubMed

    PubMed

  9. MTHFR Gene Mutation: Symptoms & Treatment - Dr. Michael Ruscio

    Dr. Michael Ruscio

  10. Can an MTHFR (Methylenetetrahydrofolate Reductase) gene mutation lead to chronic inflammation? - Dr.Oracle

    Dr.Oracle

+ 9 more sources — see the full list on Lenz

Filed Under

MTHFR gene

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