Vitamin K Rich Food Sources

Vitamin K is a fat soluble vitamin which is derived from a German word 'koagulation'.



The intestinal bacteria which normally colonize the large intestine synthesize vitamin K2 or menaquinones - an active form of vitamin K. Until recently it was believed that approximately 50% of vitamin K is produced by bacterial synthesis in the gut; however recent researches indicate that unlike previously thought the contribution of the bacterial synthesis is much lower. So it becomes important to supply enough vitamin K through diet.



Vitamin K is involved in the formation of coagulation factors or special liver proteins in the liver which then circulate in the blood and reduce the risk of bleeding or hemorrhage. Certain medication (like warfarin) that interferes with the formation of these vitamin K factors can be prescribed if you are susceptible to blood clotting. If you are on such anti-coagulant medications then it becomes important to monitor the intake of vitamin K, as this fat soluble vitamin can interfere with the action of the medication making it less effective.



Consistent intake of vitamin K is important instead of too little or too much in the diet to keep the blood clotting consistent and avoid nutrient – drug interaction.

Vitamin K1 or phylloquinone is the major dietary form of vitamin K. Vitamin K rich foods include green leafy vegetables like spinach, kale, cabbage, cauliflower, broccoli, Brussels sprouts, and soybeans. Cooked form of dark greens and broccoli provides more than one recommended dietary allowance (RDA) per serving. Other vitamin K foods include cow milk, parsley, and some vegetable oils like canola, cottonseeds, soybean and olive oil. The absorption and biological effect of vitamin K can be decreased by hydrogenation of vegetable oils. Any vitamin K supplements should be started only after consulting a specialist or a health care provider to prevent any clotting complications.

The RDA for vitamin K for adult males per day is 80 mg and for adult females per day is 65 mg. Natural form of vitamin K present in foods are only half as potent as compared to synthetic form.





Vitamin K Deficiency and Toxicity
Vitamin K deficiency as well as toxicity is very rare. New born infants, low dietary intake and people with fat malabsorption problem can suffer from vitamin K deficiency. New born babies suffer from vitamin K deficiency because their digestive tracts are not developed completely and they contain no bacteria in the gut which helps to produce vitamin K. Vitamin K deficiency symptoms include gastrointestinal bleeding, epistaxis, hematuria and menorrhagia.