How does vitamin K work?

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    Last Updated: May 16, 2025

    Vitamin K primarily functions in the γ-carboxylation of vitamin-K-dependent proteins, which are crucial for blood coagulation, vascular function, and bone metabolism. Additionally, supplemental vitamin K can enhance bone health by promoting bone formation and inhibiting bone resorption.

    In humans, the main mechanistic role of vitamin K is in the γ-carboxylation of proteins called vitamin-K-dependent proteins. Several vitamin-K-dependent proteins have been identified, and they are primarily involved in the regulation of blood coagulation, vascular function, and bone metabolism.[1][2][3][4]

    Supplementation with vitamin K can improve markers of bone health.[5][6][7] Evidence from animal studies and cell-culture studies shows that vitamin K can promote processes involved in bone formation (e.g., osteoblast differentiation and the carboxylation of osteocalcin), suppress processes involved in bone breakdown (e.g., osteoclast formation), and increase the concentration of enzymes (bone-specific alkaline phosphatase) and growth factors (IGF-1, GDF-15, etc.) involved in bone formation.[8][9][10]

    How does vitamin K work? - Examine