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    Ingredient guide · Ingredient reference

    Vitamin K2 and cancer: a dietary cohort cannot prove supplement prevention

    An observational cohort linked higher dietary menaquinone intake with lower cancer mortality, while the overall incidence association was not statistically significant. It did not randomize vitamin K2 supplements.

    Read the evidence ↓

    Supplement Science Insights Editorial Team

    Published September 23, 2026

    What the source establishes

    EPIC-Heidelberg estimated vitamin K intake using food-frequency questionnaires and followed participants for more than a decade. It compared subsequent cancer outcomes across dietary-intake categories. [1]

    Higher menaquinone intake was associated with lower cancer mortality. The overall cancer-incidence comparison did not reach statistical significance, and vitamin K1 intake showed no association. [1]

    What it does not establish

    Dietary patterns and other participant differences can confound observational associations despite adjustment. Cheese contributed substantially to estimated menaquinone intake; that does not isolate the nutrient’s effect. Funding and conflicts were not established from the abstract. [1]

    A hypothetical distinction

    Imagine people with different nutrient intakes also eat different foods and have different habits. An outcome association cannot identify which difference caused it without stronger causal evidence.

    Evidence summary — Vitamin K2 and cancer
    DetailInterpretation
    Diet questionnairesEstimated exposure
    Observational associationNot randomized treatment
    K2 supplement preventionNot established
    Vitamin K2 and cancer: a dietary cohort cannot prove supplement prevention — original article outline diagram
    Original editorial diagram of this article’s sections; no product photograph or clinical finding is depicted.

    Sources for this article

    1. Dietary vitamin K intake in relation to cancer incidence and mortality: results from the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg) - PubMed
      Source consulted: 2026-09-19. This is a reference resource, not a claim that we conducted the studies or tested a product.