What is Vitamin K

Vitamin K is a fat soluble vitamin. Its main role is the regulation of blood clots or coagulation, hence its name, derived from the German term, koagulation. It is also an active vitamin in the health of our bones.

Controlling blood clotting is extremely important in maintaining our everyday health. If we get a simple cut we need our blood to clot sufficiently to prevent excessive bleeding and form a seal to close the wound. If we clot too much it could cause a fatal blood vessel blockage, so what is vitamin K, but an essential vitamin for keeping our blood clotting at exactly the right level.

The connection of vitamin K and bone health has been well researched, with vitamin K emerging as a crucial nutrient for our bones. When taken in its correct amounts, it provides protection from bone fractures whereas when deficient in vitamin K, research has shown high risk of fractures, especially in post-menopausal women.

There are 3 forms of Vitamin K:

  • Vitamin K1 - phylloquinone, (natural)  and phytonadione, (synthetic)
  • Vitamin K2 - menaquinone
  • Vitamin K3 - menaphthone or menadione

Vitamin K1 is the only form available as a supplement of 5mg tablets or as part of a multivitamin complex.

The most common form is water-soluble chlorophyll and comes in tablet, capsule or liquid forms.

What is Vitamin K found in? Foods high in vitamin K are beef liver, green tea, turnip greens, cabbage, asparagus, lettuce, broccoli, kale and spinach.

Freezing foods decrease the vitamin K content, whereas heating does not affect its levels.

Vitamin K Benefits

  • Normal blood clotting functions
  • Strengthens bones, preventing fractures
  • Helps against bone loss in postmenopausal women
  • Assists against calcification of arteries
  • Provides the possibility of liver and prostate cancer developing

Conditions that benefit from vitamin K are excessive bleeding conditions and osteoporosis.

Vitamin K deficiency

Deficiency is rare as this vitamin is found in green leafy vegetables and also produced by bacteria in our intestines.  Antibiotics can sometimes kill this bacteria causing a mild deficiency but this usually only occurs in those with low levels to begin with.

Vitamin K Deficiency Symptoms

  • Blood clotting or bleeding
  • Bone problems
  • Calcium deposits in soft tissues including hardening of the arteries and problems with heart valve function.

Health Problems that prevent your body from absorbing Vitamin K.

  • Liver disease
  • Haemodialysis
  • Cystic fibrosis
  • Gallbladder & biliary disease
  • Celiac disease
  • Crohn’s disease
  • Serious burns
  • Taking blood-thinners, such as warfarin (Coumadin)

Those suffering from any of the above will benefit more from a multivitamin containing vitamin K as opposed to an individual vitamin K supplement. In certain circumstances, a Vitamin K injection can be given by a doctor.

Vitamin K Overdose

  • Oxidative cell and tissue damage due to free radicals can increase the risk of cancer.
  • Liver damage in infants given vitamin supplements: As it is a fat soluble vitamin we cannot excrete any excess, so it gets stored in the liver and can be extremely toxic to infants, even in small amounts.
  • Interactions with drugs: certain antibiotics, weight loss medicines and coagulants. It renders the drug Warfarin, also known as Coumadin, ineffective, increasing the risk of blood clots.

So what is Vitamin K? It is an essential vitamin for healthy blood and bones, obtained primarily from green leafy vegetables.




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