What is Vitamin K?

Vitamin K?  “I didn’t even know there was a Vitamin K?” This is usually the answer I get when I start talking about this amazing Vitamin.  Who knew there was a Vitamin K?  Well, to be honest…you should know.   Vitamin K, although discovered back in 1929, has gained new press these days because of its association with increased bone density and decreased artery calcification.  In fact, Vitamin K could be the missing link scientists have been looking for, in solving the Calcium Paradox.  (The Calcium Paradox is the simultaneous excess of calcium in one part of the body, arteries, and lack in another, bones, which may occur regardless of calcium supplementation.)  So are you eating enough foods with Vitamin K?  Do you even know what foods contain Vitamin K?  No?  Well, good thing you are reading this blog…

First:  what is Vitamin K?

Vitamin K is a group of fat-soluble Vitamins needed for blood coagulation (blood clotting) increasing metabolic pathways of bone generation and decreasing arterial calcification.  There are two main natural forms of Vitamin K; K1 and K2.

We will discuss both since they have significantly different functions.

Vitamin K1.

Vitamin K1 (also known as Phylloquinone or phytomenadione) was discovered in 1929 by Danish scientist Henrick Dam, and was referred to as Koagulationsvitamin.  As its name implies, Vitamin K1 is involved in blood coagulation.  Without K1 we could bleed to death from a simple paper cut.  Unlike your other fat-soluble vitamins (Vitamin A, D, and E) your body does not store high levels of Vitamin K1 in your tissue.  Luckily your body has a special mechanism that recycles the vitamin, so dietary requirements of Vitamin K1 are minimal.

The best sources of Vitamin K1 are green leafy plants like kale, spinach, collards, chard and broccoli.  There are also smaller amounts of K1 in roots vegetables and fruits.  My personal recommendation for someone in need of more Vitamin K1, is to drink a mineral broth.  Essentially you cook kale spinach, lettuce, chard and any other leafy greens in a pot of filtered water.  After the water turns a pretty green, you remove the vegetables and drink the broth (about a1-3 once a day).  As some of you know I am not a big fan of eating lots of above ground vegetables, especially leafy greens.  Drinking only the mineral broth and not eating the vegetable fibers will protect you from the polyunsaturated fats, vegetable toxins and cellulose found in the vegetables.  For more on this topic refer to my blog Leafy Greens- Essential or toxic?

 Vitamin K2

Vitamin K2, the main storage form in animals, is primarily used to move Calcium around the body.  To be more specific, Vitamin K2 helps Calcium move into the bones and out of the arteries—which is pretty important, right?  Vitamin K2 is sometimes referred to as the “grass-fed” Vitamin.  Westin A. Price, the dentist who discovered Vitamin K2 back in the 1940’s (Yet, he didn’t realize this and termed the Vitamin, “activator x”), noticed a huge correlation between Vitamin K2 levels and the amount of grass an animal ate.  What he realized was the more green leafy plants (grass) these animals ate the higher the Vitamin K2 content was in their milk, egg yolks, organs, and butter.  You see, K2 can be created from K1 in the testes, pancreas and arterial walls of certain animals.   And since we know there are high levels of K1 in leafy green plants (refer back to reading about K1 if I lost you here), it would make sense that this would produce more K2 levels.

Now, I know my vegetarian friends are already thinking, “If animals can produce K2 from K1, can humans do this as well?  Can humans produce our own K2, thus making eating animal foods unnecessary?”  Well, kind of…Humans can produce very small amounts of K2 by the bacteria in our intestinal tract from K1.  However, these very small amounts are not nearly enough to prevent a Vitamin K2 deficiency.  In fact, Vitamin K2 is now being looked at as an essential nutrient; since we now know we cannot produce adequate amounts by our intestinal flora.  In addition, unlike Vitamin K1, K2 is not recycled in the body, creating a daily need for this nutrient.   This means we have to get Vitamin K2 directly from our foods.

What foods contain Vitamin K2?

Vitamin K2 is primarily located in the milk fat of animals and in their organs and fatty tissue.  Good sources are foie gras (goose liver), butter, ghee, egg yolks, and grass-fed meats and organs.  Vitamin K2 can also be synthesized via fermentation in certain foods.  Dutch Gouda cheese, French brie and other cheeses are good sources of fermented foods with high Vitamin K2 levels.  Natto, or fermented soy, is also a great source of Vitamin K2.  As long as you understand the negative effects of soy, this may be the way to go if you are a vegetarian and need more K2.  The only BIG problem with natto is it taste like an old shoe and has the texture of stringy, gooey, slimy cheese…yum.

It wasn’t until 2006 that the US Department of Agriculture along with Tufts University determined the K2 content in most foods.  It has taken years of current research for scientist to realize how different K1 and K2 actually are, and that K2 needs its own daily requirements outside of K1.

The Science behind Vitamin K2.

Bone Health

Current research is linking Vitamin K2 to increased bone calcification and decrease arterial calcification.  In 2000, the team of M. Shiraki studied 241 osteoporotic patients for 2 years.   After 2 years the treated group that ingested 45mg of oral K2 had far lower incidents of repeat fractures. In 2004 another group of Japanese researchers found that vitamin K2 sustains the lumbar bone mineral density (BMD), prevented osteoporotic fractures in patients with age-related osteoporosis, and vertebral fractures in patients with glucocorticoid-induced osteoporosis.  They concluded that K2 not only increases bone formation but also suppresses bone re-absorption.  Based on these and many others studies Vitamin K2 is already used in Japan as a way to treat osteoporosis.

As I stated in my Calcium blog, there is much more to increasing bone density than just Calcium.  No nutrient works without its “team”.  Just like you cannot play football with only a quarterback, you cannot build healthy bone with only Calcium.  Your team–Magnesium, Vitamin A, Vitamin D, Vitamin E, fats, proteins, sugars and the newest member to this bone building team, Vitamin K2 –are all essential.

Cardiovascular Health

In 2004 the Rotterdam study reported that after following 4,800 individual for 10 years, those who ingested higher levels of Vitamin K2 had lower levels of cardiovascular disease and mortality.  In 2009, a team of researchers from the Netherlands analyzed research from the Prospect-EPIC cohort of over 16,000 women.  They concluded that those who ingested higher levels of K2 had far lower chances of cardiovascular heart disease (CVD).

For years people have tried to understand how the French can eat a diet rich in saturated fats and cholesterol and maintain lower levels of heart disease.  Well, the fact that the French love foie gras, butter and cheese may actually prove to their favor.  These foods are high in saturated fats, proteins, Vitamin A, D, E and Vitamin K2.  Since we now know saturated fat and cholesterol are not the bad guys we were all lead to believe – these foods may be just what the doctor ordered when it comes to the health of your heart and bones.

In addition to helping with osteoporosis and CVD, Vitamin K2 has also been linked to:

Treating Alzheimers patients;

Protecting against certain types of cancers including liver, lung, prostate and Non-Hodgkin Lymphoma;

Improving insulin sensitivity in diabetics;

Preventing joint damage; and

Increasing elasticity in skin improving wrinkles and varicose veins.

How much Vitamin K2? 

Most scientific research says we should be consuming around 45mcg of K2/day.  This is equal to about 2 ounces of raw Gouda cheese. In supplement form, 15 mg- 45 mg. of liquid K2 is recommended.  Personally, I use a combination of both: the days I eat more cheese and liver, I use less liquid K2.  The days I eat less Vitamin K2 enriched foods the more I supplement with liquid Vitamin K2.  Every person will be different, but for most people adding in a Vitamin K2 supplement should prove to be beneficial.  I prefer liquid K2 by Thorn research.

There are no known toxicity levels with Vitamin K2.  However, Vitamin K2 foods and supplements can interfere with the activity of oral anticoagulants (blood thinners) such as warfarin  (Coumadin). Patients who are using warfarin should only use vitamin K2 supplements with the knowledge of the prescribing physician.  In addition, if you are pregnant or nursing please consult your physician before adding in a Vitamin K2 supplement.

Although, Vitamin K2 research is still in its infancy, it has already proven to be a big player in your bone and cardiovascular health.  As always the best source of all vitamins and minerals is a real food diet.   However, proper supplementation of Vitamin K2 can prove to be beneficial.  If you are concerned about your bone or heart health please consult your physician.

Your Optimal Health Coach,



“I am an exercise physiologist, personal trainer, nutritional and lifestyle coach, not a medical doctor.  I do not diagnose, prescribe for, treat or claim to prevent, mitigate or cure any human disease or physical problem. I do not provide diagnosis, care treatment or rehabilitation of individuals, nor apply medical, mental health or human development principles.  I do not prescribe prescription drugs nor do I tell you to discontinue them.  I provide physical and dietary suggestions to improve health and wellness and to nourish and support normal function and structure of the body.  If you suspect any disease please consult your physician.”


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