Vitamin K is a fat-soluble vitamin.
Phylloquinone; K1; Menaquinone; K2; Menadione; K3
Vitamin K is known as the clotting vitamin, because without it blood would not clot. Some studies suggest that it helps maintain strong bones in the elderly.
The best way to get the daily requirement of vitamin K is by eating food sources. Vitamin K is found in the following foods:
Vitamin K is also made by the bacteria that line the gastrointestinal tract.
Vitamin K deficiency is very rare. It occurs when the body can't properly absorb the vitamin from the intestinal tract. Vitamin K deficiency can also occur after long-term treatment with antibiotics.
People with vitamin K deficiency are usually more likely to have bruising and bleeding.
If you take blood thinning drugs (such as anticoagulant/antiplatelet drugs), you may need to limit vitamin K foods. You should know that vitamin K or foods containing vitamin K can affect how these drugs work.
It is important for you to keep vitamin K levels in your blood about the same from day to day. Ask your health care provider how much vitamin K-containing foods you should eat.
The Recommended Dietary Allowance (RDA) for vitamins reflects how much of each vitamin most people should get each day.
The Food and Nutrition Board at the Institute of Medicine Recommended Intakes for Individuals - Adequate Intakes (AIs) for vitamin K:
Adolescents and Adults
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