Vitamin K Facts

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Like vitamin D, vitamin K can be gotten through a non-foodsource. Bacteria in the GI tract synthesize vitamin K that the body can absorb. Vitamin K's primary task is blood clotting. If blood did not clot a single pin prick could drain the entire body of all it's blood.

Adequate amounts of vitamin K can protect against hip fractures. Although, a deficiency in vitamin K is rare, antibiotics kill the vitamin K producing bacteria in the intestine, and anticoagulant drugs interfere with vitamin K metabolism and activity. A vitamin K deficiency can be fatal. It takes weeks for bacteria to form in newborns in order to produce vitamin K. A single dose of vitamin K is normally given to new born babies  to prevent hemorrhagic disease.

Vitamin K Toxicity

Vitamin K toxicity is not common, and no adverse effects have been reported with high intakes. High doses of vitamin K can reduce the effectiveness of anticoagulant drugs used to prevent blood clotting. People taking those drugs should eat vitamin K enriched foods in moderation and keep their daily intakes consistent from  day to day.

Sources: 
Understanding Nutrition Eleventh Edition

Books on Vitamin K for further research.

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