Vitamin K Dietary Sources

High-performance liquid chromatography can be used to accurately determine the major dietary form of vitamin K (phylloquinone) in foods, and food tables are being compiled for Western diets. Phylloquinone is distributed ubiquitously throughout the diet, and the range of concentrations in different food categories is very wide. In general, the relative values in vegetables confirm the known association of phylloquinone with photosynthetic tissues, with the highest values (normally in the range 400–700 μg/100 g) being found in green leafy vegetables. 

The next best sources are certain vegetable oils (e.g., soybean, rapeseed, and olive oils) which contain 50–200 μg/100 g. Some vegetable oils, such as peanut, corn, sunflower and safflower oils, have a much lower phylloquinone content (1–10 μg/100 g). The great differences between vegetable oils obviously presents problems for calculating the phylloquinone contents of oil-containing foods when the type of oil (or its storage condition) is not known.

Menaquinones seem to have a more restricted distribution in the diet than does phylloquinone. In the Western diet nutritionally significant amounts of long-chain menaquinones have been found in animal livers and fermented foods such as cheeses. Yeasts do not synthesise menaquinones and menaquinone-rich foods are those with a bacterial fermentation stage. The Japanese food natto (fermented soybeans) has a menaquinone content even higher than that of phylloquinone in green leafy vegetables.

The relative dietary importance of MK-4 is more difficult to evaluate because concentrations in foods may well depend on geographic differences in the use of menadione in animal husbandry, menadione from which MK-4 may be synthesised in animal tissues.

Another imponderable factor is the evidence that animal tissues and dairy produce may contain some MK-4 as a product of tissue synthesis from phylloquinone itself.

Knowledge of the vitamin K content of human milk has been the subject of methodologic controversies with a 10-fold variation in reported values of phylloquinone concentrations of mature human milk. Where milk sampling and analytical techniques have met certain criteria for their validity, the phylloquinone content of mature milk have generally ranged between 1 and 4 μg/l, with average concentrations near the lower end of this range. 

However, there is considerable intra- and inter-subject variation, and levels higher are in colostral milk than in mature milk. Menaquinone concentrations in human milk have not been accurately determined but appear to be much lower than those of phylloquinone. Phylloquinone concentrations in infant formula milk range from 3 to 16 μg/l

in unsupplemented formulas and up to 100 μg/l in fortified formulas. Nowadays most formulas are fortified; typical phylloquinone concentrations are about 50 μg/l.

References:

Shearer, M.J., Bach, A. & Kohlmeier, M. 1996. Chemistry, nutritional sources, tissue distribution and metabolism of vitamin K with special reference to bone health. J. Nutr., 126: 1181S-6S.

Booth, S.L., Davidson, K.W. & Sadowski, J.A. 1994. Evaluation of an HPLC method for the determination of phylloquinone (vitamin K1) in various food matrices. J. Agri. Food Chem., 42: 295-300.

Booth, S.L., Sadowski, J.A., Weihrauch, J.L. & Ferland, G. 1993. Vitamin K1 (phylloquinone) content of foods: a provisional table. J. Food Composition Anal., 6: 109-20.

Thijssen, H.H.W. & Drittij-Reijnders, M.J. 1994. Vitamin K distribution in rat tissues: dietary phylloquinone is a source of tissue menaquinone-4. Br. J. Nutr., 72: 415-25.

Canfield, L.M. & Hopkinson, J.M. 1989. State of the art vitamin K in Human milk. J Pediatr. Gastroenterol. Nutr., 430-41.

von Kries, R., Shearer, M., McCarthy, P.T., Haug, M., Harzer, G. & Göbel, U. 1987. Vitamin K1 content of maternal milk: influence of the stage of lactation, lipid composition, and vitamin K1 supplements given to the mother. Pediatr. Res., 22: 513-7.

Greer, F.R. Marshall, S. Cherry, J. & Suttie, J.W. 1991. Vitamin K status of lactating mothers, Human milk and breast-feeding infants. Pediatr., 88: 751-6.

Haroon, Y. 1982. The content of phylloquinone (vitamin K1) in Human milk, cows’ milk and infant formula foods determined by high-performance liquid chromatography. J. Nutr., 112: 1105-17.