Vitamin K is a fat soluble vitamin that is essential for human health and yet many people do not get enough of this life saving vitamin.

Vitamin K has many roles –

  • It is essential for blood clotting so you do not bleed to death if you suffer trauma
  • It is essential for strong bones
  • It slows the calcification of tissues
  • It can destroy certain types of cancer cells

There are 3 types of Vitamin K

  • Vitamin K1 is known as phylloquinone
  • Vitamin K2 comprises a group of vitamins called the menaquinones
  • Vitamin K3 (or menadione) is a synthetic form of vitamin K.

Sources of Vitamin K

  • Vitamin K1 is present in green vegetables such as broccoli, kale, spinach and other leafy greens, canola, soybean, and other plant oils
  • Vitamin K2 is present in liver, butter, chicken, egg yolk, certain cheeses, and fermented soybean products such as natto. Intestinal bacteria in the intestines also synthesize it.

Foods rich in vitamin K must be consumed regularly as the liver stores only limited amounts. Significant deficiencies of vitamin K are not common in people eating healthy diets. Certain health problems can lead to vitamin K deficiency or an increased need for vitamin K; these include:

A Poor Diet
Intestinal diseases such as Celiac, Crohn’s Disease, Ulcerative colitis, pancreatitis, gastric surgery, leaky gut or other problems that reduce nutrient absorption
Liver disease because this reduces vitamin K storage
Some medications, such as antibiotics, statins, Xenical, mineral oil and blood thinners.

Deficiencies of vitamin K can increase the risk of bone loss (osteoporosis), hardening of the arteries (arteriosclerosis), and cancer.

Bone Health
I encourage all people with low bone density (osteopenia or osteoporosis) to take a supplement of vitamin K 2. In Japan, vitamin K has been an approved treatment for osteoporosis since 1995.

Protecting Arteries from Calcification
We know that vitamin K helps direct calcium to the bone and holds it there. Vitamin K also helps to keep calcium out of the linings of arteries and other body tissues, where it can build up to dangerous levels. As we age our arteries become stiffer and harder as the body deposits calcium into the artery walls. This problem is known as arteriosclerosis, and is a risk factor for heart disease, kidney disease, high blood pressure and stroke.
More studies are needed, but it appears that by regulating calcium, vitamin K simultaneously reduces the risk of both osteoporosis and hardened arteries.

Cancer Prevention
New research suggests that vitamin K may help improve survival rates for those suffering with cancer. Vitamin K1 appears to play a role in cell replication and can inhibit unhealthy cell growth.
Vitamin K2 encourages the suicide (apoptosis) of certain types of cancer cells (pancreatic, ovarian cells and leukemia cells). This new research means that vitamin K may one day be prescribed to direct cancer cells to stop their aggressive and unregulated growth.

 

Recommended Dosages of Vitamin K

The average adult ingests 59-82 micrograms (mcg) of vitamin K per day. This is less than desirable for optimal health. The Food and Nutrition Board of the National Institute of Medicine, sets the adequate daily intake as 120 mcg for men and 90 mcg for women. Greater amounts than this may help protect against osteoporosis and calcification of the arteries. Supplements containing from 25 mcg up to 10 milligrams (mg) of the vitamin are readily available.

The Food and Nutrition Board states that, “No adverse effects associated with vitamin K consumption from food or supplements have been reported in humans or animals.”

Caution: Blood thinning drugs (especially coumarin drugs) are affected by vitamin K. Thus you should check with your own doctor before taking supplements of vitamin K.

Vitamin K2 Reduces Growth and Invasion of Human Liver Cancer Cells.

Vitamin K2 may be a promising therapeutic treatment for the management of liver cancer. Liver cancer is known as Hepatic Cell Carcinoma (HCC).
A study examined the effects and mechanisms of the retardation of liver cancer cell growth induced by a form of vitamin K 2 known as MK-4. The results were very positive; the rates of venous invasion by liver cancer cells in the vitamin K–treated group were 2% at 1 year and 13% at 2 years; the rates were 21% at 1 year and 55% at 2 years in the control group who did not receive vitamin K (P = .01).

Oral administration of vitamin K2 was shown to reduce the ability of liver cancer cells to invade and spread via the veins in the liver (portal venous system). In this study, it was shown that vitamin K2 inhibits the invasiveness and growth of liver cancer (HCC) cells. This could be because high doses of vitamin K2 might alter the effects of key signalling molecules which stimulate cancer cells to grow.

The benefit of vitamin K2 was apparent only at high doses, which is consistent with the finding that high doses of vitamin K2 were needed to inhibit liver cancer cell (HCC) activities. This study was reported in the journal Hepatology and produced results which suggest that high-dose vitamin K2 treatment can function as an inhibitor of primary liver cancer (HCC) cell growth.

Most of the present studies were performed using relatively high doses of vitamin K2. In Japan, vitamin K2 is usually administered to osteoporotic patients at a dose of 45 mg/d. Several reports have showed that orally administered vitamin K2 is concentrated in the liver, and the concentration in liver tissues is at least 10 times greater than in plasma. Thus cancer cells situated in the liver might be exposed to higher concentrations of vitamin K2 because of more prolonged exposure and greater uptake. The data from this study indicates that vitamin K2 supplementation actually reduces the growth and invasion of liver cancer (HCC) cells.

Vitamin K2 is used by doctors in Japan to treat osteoporosis either by itself or combined with vitamin D3. Vitamin K 2 has no known adult human toxicity, which makes orally administered vitamin K2 a very promising treatment for preventing cancer and for keeping tumours inactive (dormant). More clinical trials are in progress to evaluate vitamin K2 in patients with primary liver cancer. Future trials may determine the efficacy of vitamin K2 for other types of cancer.

 

In Summary

Vitamin K is best known for its role in the liver’s synthesis of blood clotting proteins. New research, has demonstrated that vitamin K may play many vital roles in the body to ward off diseases. The role of vitamin K in preventing osteoporosis, softening the arteries to reduce cardiovascular disease and killing cancer cells is relatively new and unfortunately not all doctors are aware of this new research. Vitamin K has also been shown to improve skin health and reduce Alzheimer’s disease and diabetes. Vitamin K has been recognized as an antioxidant with anti-inflammatory properties. Thus Vitamin K should be part of your tool kit to slow down the ageing process.

References


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