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Vitamin K - Phylloquinone or Menaquinone, Menadione

Vitamin K is a fat soluble vitamin which is rarely deficient. Healthy bowel bacteria ensure adequate amounts of vitamin K. Natural yoghurt which provides 'healthy' bowel bacteria is a good source of vitamin K.

The main function of Vitamin K is in the regulation of blood clotting. Chronic nose bleeds may respond to the therapeutic use of vitamin K.

The functions of vitamin K

Vitamin K is essential for:

There are some indications that vitamin K may decrease the incidence or severity of osteoporosis by slowing bone loss.

The symptoms and signs of vitamin K deficiency

A deficiency of vitamin K in newborn babies results in hemorrhagic disease. Deficiency can also result in postoperative bleeding and hematuria. Muscle hematomas and intra-cranial hemorrhages have also been reported.

A shortage of this vitamin may manifest itself in:

Chronic diarrhea is both a symptom of the deficiency and a cause of the deficiency.

Food sources of vitamin K

Vitamin K is found in leafy vegetables, broccoli and Brussels sprouts, cheese, egg yolks, kelp and liver. It is also found in asparagus, coffee, bacon and green tea.

How much is needed?

The dosage below is the Recommended Dietary Allowance (RDA), but be aware that this dosage is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the toxicity level must be kept in mind.

Males 80 micrograms per day and females 70 micrograms per day.

Toxicity and symptoms of high intake

Toxicity does not easily occur with normal dietary intake of this vitamin.

It is not recommended that you take more than 500mcg of synthetic vitamin K (mendadione). High to toxic uptake of the synthetic form can cause flushing and sweating, jaundice and anemia.

If you are taking an anti-coagulant medication (to prevent blood clotting) consult your medical practitioner before taking vitamin K supplement.

Special notes

Dietary fat is necessary for the absorption of this vitamin, so any problems with fat digestion will discourage vitamin K absorption. Anything else that affects the activity of the bowels including long courses of antibiotics will prevent the absorption of vitamin K.

This nutrient can be destroyed by freezing and radiation as well as air pollution. Absorption may be decreased when rancid fats are present, as well as excessive refined sugar, antibiotics, high dosages of vitamin E, or calcium and mineral oils.

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Bland, J. 1996, Contemporary Nutrition. J & B Associates.

Davies, S. and A. Stewart., 1997, Nutritional Medicine. Pan.

Holden, S., Hudson, K., Tilman, J. & D. Wolf, 2003, The Ultimate Guide to Health from Nature. Asrolog Publication.

Pressman, A. and S. Buff, 2000, The Complete Idiot's Guide to Vitamins and Minerals. (2nd Ed.) Alpha Books.

Soothill, R. 1996, The Choice Guide to Vitamins and Minerals. A Choice Book Publication.

Sullivan, K. 2002, Vitamins and Minerals: A Practical Approach to a Health Diet and Safe Supplementation. Harper Collins.

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