Vitamin K2 is found in chicken egg yolk, butter, cow liver, certain cheeses and fermented soybean products such as natto, the best source of vitamin K2.
Vitamin K2 is the most biologically active form of vitamin K, a vitamin that has anticancer properties, but is also known as "the forgotten vitamin" as very few supplements on the market contain it, and those that do contain very small amounts.
It is also the most beneficial form of vitamin K for bone health maximization.
Synthetic vitamin K2 (menatetrenone, or menaquinone-4 (MK-4)) may improve a group of blood disorders known as myelodysplastic syndromes (MDS).
It also ameliorates cytopenia in patients with refractory anemia of myelodysplastic syndrome.
Vitamin K2 and its derivatives induce apoptosis in leukemia (CML) and lung cancer cells and enhance the effect of all-trans retinoic acid.
Vitamin K2 is also useful in the treatment of liver, colon, stomach, nasopharynx, breast, prostate, lymphoma, bone and oral cancers.
Synthetic vitamin K2 (menatetrenone, or menaquinone-4 (MK-4)) is hard to find at local health food stores, but high dose supplements can easily be purchased over the internet, or can be obtained by prescription. The doses used for myelodysplasia and leukemia range from 20 mg to 135 mgs per day, with 45 mgs per day being the average. The time required before obtaining some hematologic improvement after initiation of vitamin K2 therapy ranges from 1 to 3 months.
It should be taken with a fat, such as organic coconut milk, to make it more bioavailable, or should come in a gel cap, like vitamins D and E.
Vitamin K2 is completely non-toxic and has no side effects, even at very large doses.
Natto is particularly rich in the highly bioavailable form of vitamin K2 called menaquinone-7 (MK-7).
Natto provides natural vitamin K2 as menaquinone-7 (MK-7), which is the most bioavailable form of K2 available, and also has the longest half-life in the blood. This provides optimal vitamin K status with a recommended daily dose of just 45-90 mcg.
You can buy the natural vitamin K2 through Dr. Mercola:
Fight Cancer With Vitamin K
Natto: The Fermented Soybean That Fights Cancer and Hot Flashes.
Vitamin K2 has also been linked to osteoblasts, the cells that generate or "lay down" bone and produce a specific protein known as osteocalcin:
Vitamin K2 Prevents and Reverses Bone Loss
Life Extension Magazine article on Vitamin K2, March 2008
Vitamin K2 is normally produced by bacteria in the intestines, and dietary deficiency is rare, unless the intestines are heavily damaged or are unable to absorb the molecule, such as in malabsorption syndromes, or through the chronic use of drugs/medications, alcohol or antibiotics.
Natto also contains nattokinase, a very popular enzyme used against cancer and clots.
UPDATE 07/03/08: Since I posted this blog entry, there have been numerous visits to my site by people searching for natural treatments for myelodysplasia and leukemia, and iHerb keeps running out of it's high-dose Carlson Vitamin K2. Please put yourself on the list to be notified when they are back in stock. It seems that they re-stock it every couple of days, but it sells out very fast, within hours. So, order fast when you are notified by email that they have it in stock again! You should take Carlson K2 with an oil to make it more bioavailable, as it is synthetic.
LEF Nutritional Supplementation for Specific Forms of Leukemia
For non-leukemia cancers:
Kiran Krishnan (see the comments to this blog entry) recommends Dr. Mercola's vitamin K2 or Swanson's K2 called MenaQ7, at 100 mcg. per day.
Safety of Vitamin K2 with Respect to Hypercoagulation in Humans:
From a large number of clinical trials using dosages in excess of 40 mg/day, there were no reports of side effects associated with any type of hypercoagulable state. (1,27,35.36) Both animal and clinical studies support the conclusion that vitamin K2 has no abnormal hemostatic activity. In one study, vitamin K2 given to rats at a dose of 250 mg/kg body weight per day for 10 days resulted in no appreciable change in blood coagulation characteristics or platelet aggregation. (37)