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Cited by 423

The DOI matches its Crossref record; 19 of the 19 references it cites were found in a registry or an index.

Vitamin K–containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7

Open access
Schurgers, Leon J., Teunissen, Kirsten J. F., Hamulyák, Karly, Knapen, Marjo H. J., Vik, Hogne, Vermeer, Cees·2007·Blood

Abstract

Vitamin K is a cofactor in the production of blood coagulation factors (in the liver), osteocalcin (in bone), and matrix Gla protein (cartilage and vessel wall). Accumulating evidence suggests that for optimal bone and vascular health, relatively high intakes of vitamin K are required. The synthetic short-chain vitamin K1 is commonly used in food supplements, but recently the natural long-chain menaquinone-7 (MK-7) has also become available as an over-the-counter (OTC) supplement. The purpose of this paper was to compare in healthy volunteers the absorption and efficacy of K1 and MK-7. Serum vitamin K species were used as a marker for absorption and osteocalcin carboxylation as a marker for activity. Both K1 and MK-7 were absorbed well, with peak serum concentrations at 4 hours after intake. A major difference between the 2 vitamin K species is the very long half-life time of MK-7, resulting in much more stable serum levels, and accumulation of MK-7 to higher levels (7- to 8-fold) during prolonged intake. MK-7 induced more complete carboxylation of osteocalcin, and hematologists should be aware that preparations supplying 50 μg/d or more of MK-7 may interfere with oral anticoagulant treatment in a clinically relevant way.

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Crossref · 10.1182/blood-2006-08-040709

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Metadata

Authors
Schurgers, L. J., Teunissen, K. J. F., Hamulyák, K., Knapen, M. H. J., Vik, H., & Vermeer, C.
Venue
Blood
Published
2006-12-07
Volume
109
Issue
8
Pages
3279-3283
ISSN
  • 0006-4971 (ISSN-L)
  • 1528-0020
OpenAlex
W2144461421
Cited by
423
References
19
FWCI
9.72
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: Vitamin K–containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7. https://app.cochat.ai/papers/10.1182/blood-2006-08-040709
The paper
Schurgers, L. J., Teunissen, K. J. F., Hamulyák, K., Knapen, M. H. J., Vik, H., & Vermeer, C. (2007). Vitamin K–containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7. Blood. https://doi.org/10.1182/blood-2006-08-040709

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