Vitamin K is much more than a blood clotting agent. Vitamin K improves bone density, aids in preventing hardening of the arteries, and is a stronger antioxidant than vitamin E or coenzyme Q10. There are 3 known forms of vitamin K. K1 is found in dark green leafy vegetables. K2 is synthesized in the body by the healthy bacteria in the gut and is found in naturally fermented foods. K3 is synthetic and tends to generate excess free radicals and should be avoided.
Although vitamin K is fat soluble, it is not stored in the body. Deficiency of vitamin K is actually common. Antibiotics, aspirin, cholesterol reducing drugs, and hydrogenated oils are known to interfere with or deplete vitamin K.
Vitamin K is actually a modulator of blood clotting. Too much vitamin K will not cause too much blood clotting because the process is self regulated in the body. Vitamin K will also prevent blood clots by preventing platelet aggregation which is a separate process from coagulation. Platelet aggregation has to do with free radical damage, whereas coagulation is about calcium level in the cells.
New research on vitamin K is showing that K helps to keep calcium in the bones and out of the arteries. Vitamin K works on a specific form of protein that controls calcium. With enough vitamin K, this protein known as osteocalcin can hold onto the calcium and keep it from drifting out of the bones into soft tissue. When there is not enough vitamin K in the body to "carboxylate" the osteocalcin, calcium leaves the bones which then become porous.