Vitamin K occurs in, at least two major forms- Vitamin K1 & Vitamin K2.
- Vitamin K1 is found mainly in- fresh green vegetables, particularly dark green ones & in some fruits. Cow’s milk is a richer source of, vitamin K than human milk.
- Vitamin K2 is synthesized by- intestinal bacteria; which usually provide, an adequate supply in man. Long-term administration doses for more than a week, may temporarily suppress the normal intestinal flora & may cause a deficiency of, vitamin K.
- Vitamin K is stored in the liver.
The role of Vitamin K is-
to stimulate production or release of, certain coagulation factors. Invitamin K deficiency, the prothrombin content of blood, is markedly decreased & the blood clotting time, is considerably prolonged.The vitamin K requirement of man is, met by a combination
The daily requirement of it-
- for man- appears to, be about 0.003 mg/kg for the adult.
- Newborn infants- tend to be deficient in vitamin K, due to minimal stores of prothrombin at birth & lack of an established intestinal flora.
- Soon after birth, all infants or those at increase risk- should receive a single intramuscular dose of, a vitamin K preparation; by way of prophylaxis.