Dietary vitamin K1 and stability of oral anticoagulation: proposal of a diet with constant vitamin K1 content

Thromb Haemost. 1997 Mar;77(3):504-9.


Case reports cited in Medline or Biological Abstracts (1966-1996) were reviewed to evaluate the impact of vitamin K1 dietary intake on the stability of anticoagulant control in patients using coumarin derivatives. Reported nutrient-drug interactions cannot always be explained by the vitamin K1 content of the food items. However, metabolic data indicate that a consistent dietary intake of vitamin K is important to attain a daily equilibrium in vitamin K status. We report a diet that provides a stable intake of vitamin K1 equivalent to the current U.S. Recommended Dietary Allowance, using food composition data derived from high-performance liquid chromatography. Inconsistencies in the published literature indicate that prospective clinical studies should be undertaken to clarify the putative dietary vitamin K1-coumarin interaction. The dietary guidelines reported here may be used in such studies.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Administration, Oral
  • Anticoagulants / administration & dosage
  • Anticoagulants / adverse effects
  • Anticoagulants / therapeutic use*
  • Coumarins / administration & dosage
  • Coumarins / adverse effects
  • Coumarins / therapeutic use*
  • Diet*
  • Drug Interactions
  • Humans
  • Nutritional Status
  • Vitamin K 1 / pharmacology*
  • Warfarin / administration & dosage
  • Warfarin / adverse effects
  • Warfarin / therapeutic use


  • Anticoagulants
  • Coumarins
  • Warfarin
  • Vitamin K 1