Vitamin K: Role in the Body & Benefits

Role in the Body
Vitamin K is involved in blood clotting. It is necessary for the synthesis of prothrombin, which after various conversions forms the blood clot. Vitamin K is also necessary for bone formation and the making of new bone cells. While vitamin K can be obtained from dietary sources, bacteria that live in our intestines make much of the vitamin.

Dietary Sources
Vitamin K is found in dark leafy vegetables such as spinach, turnip greens, broccoli, green cabbage as well as in tomatoes, liver, egg yolks, whole wheat, fruits, cheese, ham and beef.

Who Is at Risk for Deficiency?
You may be at risk if you have liver disease, Crohn's disease, if you have been on antibiotics for an extended period of time, or take certain cholesterol-lowering drugs.

Benefits
Vitamin K is necessary for preventing, and may slow down, osteoporosis.

Cautions
Large doses should not be taken during the last month of pregnancy. Large doses of synthetic vitamin K can be toxic and cause liver damage. Antibiotics interfere with the absorption of vitamin K and kill the bacteria in the intestine responsible for synthesizing much of the body's vitamin K.