Vitamin K plays an essential role in hemostasis (blood clotting) and is involved in bone metabolism. Deficiency may occur with inadequate dietary intake, malabsorption syndrome and chronic liver disease. Deficiency may cause osteoporosis (with an increased risk of fractures) and hemorrhaging (easy bleeding under the skin, from the stomach and intestines, the nose, urinary bladder and uterus). Rich sources are green leafy vegetables, vegetable oils, hemp seeds, liver, chicken egg yolk, and fish meal. It is also produced by the bacteria in our intestines. Recommended daily allowance is 5-80 micrograms/day based on age. (For more detailed information, please visit ISM’s searchable database: Nutraceutical Search.)
In patients with viral-induced liver cirrhosis, less than 10% of those patients who took vitamin K2 developed liver cancer, compared to 47% in patients who did not take the supplement. [News Release: Protection against arterial calcification, bone loss, cancer and aging! LifeExtension January 2009.]
An improved vitamin K2 status may reduce the risk of prostate cancer. The potential benefits of K2 were more pronounced for advanced prostate cancer. o Nimptsch, K, Rohrmann, S, Nieters, A, & Linseisen, J (2009). Serum undercarboxylated osteocalcin as biomarker of vitamin K intake and risk of prostate cancer: a nested case-control study in the Heidelberg cohort of the European prospective investigation into cancer and nutrition. [Cancer Epidemiology, Biomarkers & Prevention, 18(1), 49-56.]
In a study of 11,319 men followed for 8.6 years, those who consumed a higher daily intake of vitamin K2 had a 63% reduction in the incidence of advanced prostate cancer. [News Release: Protection against arterial calcification, bone loss, cancer and aging! LifeExtension January 2009.]
An increased intake of vitamin K2 (but not K1) may reduce the risk of prostate cancer by 35 per cent . o Nimptsch, K, Rohrmann, S, & Linseisen , J (2008). Dietary intake of vitamin K and risk of prostate cancer in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg). [Am J Clin Nutr, 87(4), 985-92.]
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