Vitamin K is a fat soluble vitamin that plays an important role in bone health (especially postmenopausal), formation of coagulation proteins, and prevention of calcification of blood vessels. Vitamin K is also produced naturally by bacteria in the intestines, but this process contributes significantly less vitamin K than previously thought. Dietary sources provide most of the vitamin K the body needs. Good sources include kale, spinach, collard greens, cabbage, broccoli, parsley, green tea, peas, beans and oils.
Deficiency can lead to excessive bleeding which may begin as oozing from the nose or gums and can extend to bleeding in the digestive tract, hemorrhaging, very heavy menstrual bleeding and resultant anemia. Deficiency can also lead to loss of bone and excess deposition of calcium in the arteries and heart valves. In infants deficiency can cause hemorrhagic disease of newborns.