What are the Sources of Vitamin K?
As mentioned above, in plants, the only important molecular 'form of vitamin K is phylloquinone. Phylloquinone is distributed ubiquitously throughout the diet, and the range of concentrations in different food categories is very wide. In general, the highest values (normally in the range 400-700 mg/100 g) are found in green leafy vegetables (such as spinach, cauliflower, cabbage and lettuce). The next best sources are certain vegetable oils (e.g. soybean, rapeseed and olive), which contain 50-200 mg/100g, other vegetable oils, such as peanut, corn, sunflower and safflower, however, contain much lower amounts of phylloquinone (1-10 mg/100 g). The great differences between vegetable oils with respect to vitamin K content obviously present problems for calculating the phylloquinone contents of oil containing foods when the type of oil is not known. Other good sources include animal foods such as egg yolk, milk and organ meats like liver.