VITAMIN K’s two primary roles are to facilitate blood clotting (coagulation), and to enhance osteocalcin’s action in maintaining a healthy balance between bone formation and bone breakdown. Thus, Vit K helps to keep the blood flowing and to coagulate when necessary. Furthermore, Vit K promotes healthy bone mass.
VIT K deficiency may lead to bleeding gums, nose bleeds, excessively heavy menses (periods), and internal bleeding (hemorrhages), such as under the skin (easy bruising) or anywhere inside the body. Intestinal bleeding may show up as bloody stool (melena), and bleeding in the kidneys produces blood in the urine. In the elderly, a Vit K deficiency may lead to an increased susceptibility to bone fractures and soft bones (osteomalacia).
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Vit K is given to the newborn to ward of Vit K deficiency since newborns cannot make their own Vit K, and may not receive enough via the placenta while still developing in the uterus, or after birth while breastfeeding. Severe Vit K may lead to hemorrhagic disease. While up to 50% of infants less than 5 days old, show some level of Vit K deficiency, only 0.25% – 1.7% of infants develop classic hemorrhagic disease, manifesting in bleeding around the umbilicus, skin, nose, digestive tract. and, rarely, as bleeding of the brain (intracranial hemorrhage). Approximately 20 infants in 100,000 develop late onset hemorrhagic disease as late as six months after birth. In these infants, the rate of acute intracranial bleeding is quite high.