Blood flow is necessary for survival, thus mechanisms exist in the body to ensure that blood flow is maintained. Hemostasis is the mechanism used by the body to sustain blood flow; its components include clotting factors, platelets, substances released from cells that line blood vessels, and vasoconstriction. Vitamins facilitate the activation of clotting factors and injury repair.
Blood
Blood is a tissue composed of a liquid portion called plasma and a cellular portion called the formed elements. The plasma is 90% water; it also contains other important molecules such as clotting factors, carrier proteins, antibodies and hormones that circulate in blood. The formed elements consist of red blood cells, white blood cells and platelets.
Platelets
Platelets are cell fragments or derivatives of a larger cell called the megakaryocyte; it is produced in the bone marrow. Platelets float around in the blood until they reach a site of blood vessel injury. Collagen contained in the blood vessel wall is exposed in a blood vessel injury and is a trigger for the coagulation cascade involving the clotting factors. This coagulation cascade leads to the production of molecules that activate platelet aggregation, thus forming clots.
Clotting factors
All clotting factors are made in and released from the liver except the vWF or von Williebrand factor, which is made by endothelial cells. Endothelial cells line the lumen of the blood vessels. The vWF stick to exposed collagen and also to platelets and by doing so, helps in forming a plug that closes the gap created by injury.
Vitamin K
Vitamin K is synthesized by bacteria in the intestines; it is also absorbed from green leafy vegetables such as broccoli, kale, asparagus and brussels sprouts. Vitamin K is needed for the activation of several clotting factors produced by the liver, which include factors II, VII, IX, X, protein C and protein S. Vitamin K activation is inhibited by warfarin.
