Facts

	Vitamin K, also known as the "anti-haemorrhaging" vitamin, contains three main types: vitamin K-1, K-2, and K-3. K-1 and K-2 are produced naturally while k-3 is synthetically produced.
	It requires a small amount of fat in order to be absorbed.
	A deficiency of vitamin K is possible in newborns due to low vitamin K status at birth and a sterile gut unable to produce this vitamin. In the United States, newborns are often given an injection of vitamin K shortly after birth.

Functions

	Vitamin K is important for the formation of prothrombonin, a chemical necessary for blood clotting.1
	It also is necessary for proper bone formation and repair, helps synthesise the protein in bone tissue in which the crystallisation of calcium occurs, which has implications for osteoporosis.
	It is involved in converting glucose to glycogen in the intestines for storage in the liver in addition to promoting optimal liver function and preventing the occurrence of certain cancers that attack the inner linings of the organs.2

Requirements
No Recommended Daily Allowance has been set for Vitamin K.


Signs of Deficiency
Symptoms include: abnormal bleeding, excessive bruising, diarrhoea, miscarriage and nosebleeds.1

Signs of Toxicity
Natural vitamin K does not pose a toxicity threat.1 Synthetic vitamin K has caused toxicity when it was injected in pregnant women. Synthetic vitamin K toxicity symptoms include: flushing, sweating and chest constrictions.1


Current Research

Heart Disease
There is a significant body of research regarding the positive role of vitamin E and cardiovascular disease. In a 4-year study of 39,000 professionals, Harvard researchers found that men who supplemented their diets with at least 100 IU daily had a 39% lower risk of developing coronary artery disease than men who did not. Similar findings were noted for women.4

Osteoporosis
Vitamin K is involved in the manufacture of two proteins, osteocalcin and matrix Gla protein, which are involved in bone metabolism. Researchers at the University of Wisconsin at Madison, reviewed literature involving vitamin K and bone health. They found that blood concentration levels of vitamin K are lower in elderly persons with bone fractures associated with osteoporosis. Researchers speculate that vitamin K indirectly affects the skeletal system by regulating the rate at which urinary calcium is excreted.4 Several population studies are underway investigating if increased vitamin K slows bone loss.5

Vitamins Home