Vitamin K2: A Little Known Vitamin That We Now Know Reverses and Prevents Artery Calcification and Promotes Bone Matrix Calcification

A “vitamin” is a nutrient essential for life. We are well-acquainted with most vitamins, such as vitamin A, the B-vitamins, and vitamins C, D, and E. Each has a well-known and essential role in support of vital tissue functions, and each must be ingested from particular food sources, with the exception of vitamin D which can be synthesized from cholesterol in our skin tissues from direct sunlight.  

Vitamin K is lesser-known. Vitamin K was discovered in the early 1930s as an essential vitamin necessary to enable the production of blood clot proteins within the liver. Vitamin K deficiency is rare as green vegetables are the principal diet source. In this role, vitamin K is well-known. 

A prescribed medication called “warfarin” was eventually invented as a medication that inhibits blood clot protein productions. Warfarin disables this vitamin K action and thus diminishes the formation of essential blood clot proteins. When prescribed, this action effectively disables blood clot formation for the person in whom a blood clot has spontaneously formed or may form in their blood vessels or heart. Such vitamin K inhibitory action by “warfarin” is intended to be beneficial and protective when prescribed, and it is beneficial and protective, though warfarin daily dosing must be monitored very closely and adjusted on occasion by health care personnel to achieve safe precise effectiveness.

The molecular scientists who have studied vitamin K in deep detail have learned that vitamin K has two different molecular structures that exist independently in nature. As such, the vitamin K “family” is now understood as “vitamin K-1” and “vitamin K-2.”  Vitamin K-1 is the specific molecule form which is essential for blood clot protein production. Vitamin K-1 exerts its actions in liver cells. 

Vitamin K-2 has molecular structure differences from vitamin K-1, which makes K-2 have vital function differences than vitamin K-1. Specifically, K-1 exerts its molecular actions on distinct receptors located on blood vessel walls and on another receptor located within the bone matrix. Very specifically, the special union of K-2 to the blood vessel wall molecule (named Matrix GLA) inhibits the deposit of plasma calcium molecules into blood vessel cell walls. It is significant that our blood plasma carries calcium absorbed from our diet directly to bone and muscle, but calcium easily deposits onto blood vessel walls, particularly if the blood vessel wall is collecting fat and cholesterol plaques. 

Thus, vitamin K-2 acts as an essential cofactor to prevent calcification of our blood vessels, a nearly universal pathological change of arteries associated with aging. This vital fact is only recently understood. Vitamin K-2 acts to prevent calcification of arteries, and it can reverse calcification after it happens. Secondly, vitamin K-2 also uniquely activates a hormone in our bones named osteocalcin. This activation step is necessary and essential for the transfer of circulating calcium out of plasma into the bone matrix. Thus vitamin K-2 facilitates bone formation and repair. K-2 works in harmony with vitamin D-3 for this process. 

Think about it! These actions of vitamin K-2 are the most amazing biological synchrony: With adequate vitamin K-2 presence, calcium is prohibited from binding to our vascular cell walls - preventing calcified arteries - and in synchrony, calcium is migrated out of our plasma into the bone matrix for bone building and repair.  

Vitamin K-2 is unique and distinct and is without question extremely beneficial to health and wellness.

As of 2020, vitamin K-2 has emerged as one of the most-studied vitamins. The National Library of Medicine now contains over 4000 publications centering on vitamin K-2 research over the past 25 years. It must be shared that vitamin K-2 is much less present in usually eaten foods than the other essential vitamins. Specifically, The National Academy of Medicine states that the usual Western diet supplies less than 25% of the vitamin K-2 needed. 

The only foods with vitamin K-2 are heavily fat-laden meats, natto fermented soy, and fermented cheeses. Natto Soy is heavily fermented with a bacteria that produces K-2, as are some but not all fermented cheeses. Fat-laden meats are less and less consumed in the 21st century. Accordingly, with this new expanding knowledge base, vitamin K-2 supplementation has become strongly recommended by many Nutrition Councils and Experts worldwide.

Here are a few research study conclusions:

• Specific research studies supplying vitamin K-2 as a capsule supplement have shown that vitamin K-2 supplements in the context of usual diet clearly improve bone and cardiovascular health, whereas Vitamin K-1 supplementation had no significant benefits.  

• In one study spanning nearly 10 years, people with extra supplement intake of vitamin K-2 were 50% less likely to develop artery calcification and had a 57% lower risk of dying from heart disease.  

• Another study of approximately 16,000 women demonstrated that for every 10 mcg of vitamin K-2 they consumed per day, heart disease risk was reduced by 9%. Intake of 45 mcg reduced heart disease by almost 40% compared to vitamin intake lacking K-2.

• A recently published prospective study of approximately 3000 Norwegian adults rigorously analyzed dietary intake of vitamin K-1 versus Vitamin K-2 and the development of coronary heart disease. Food diaries were extensive and the principal food sources of vitamin K-2 were Natto Fermented Soy and Fermented Cheeses.  Over the 10 year study period, a higher dietary intake of vitamin K-2 was associated with a statistically significant lower risk and occurrence of coronary heart disease compared to low or usual intake of vitamin K-2 foods.

• Unfortunately, it has become clinically apparent that warfarin use is associated with progressive vascular calcification, which can become major. In one well-done laboratory animal study, warfarin-induced aortic calcification was reduced and prohibited by regular administration of vitamin K-2 to the animals. This illustrates 1) that warfarin-inhibition of vitamin K includes both vitamin K-1 and vitamin K-2, leading to progressive arterial calcification, and 2) that supplemental provision of vitamin K-2 blocks and reverses this dreaded vascular disease - without interfering with warfarin’s anticoagulant effect.

• A recent 10-year European study of 4,800 individuals aged 55 and older revealed clear associations between low vitamin K-2 intake and major aortic calcification. The association was strong and has propelled strong recommendations to promote daily vitamin K-2 supplementation.

• Bone disease is reduced by daily vitamin K-2 intake also. Population studies among women in Japan have demonstrated that regular moderately high intake of vitamin K-2 is associated with a significantly lower risk of hip fractures compared to low irregular intake of any vitamin K-2. Multiple studies in elderly women have also demonstrated that supplemental vitamin K-2 intake reduces bone fractures and limits osteoporosis.

• Interestingly, additional research has produced evidence that vitamin K-2 plus vitamin D-3 supplementation is superior in support of bone health compared to vitamin D-3 supplements alone. Several studies have shown that spinal fractures and hip fractures are significantly reduced over time and bone mineral densities are significantly higher over time with regular intake of vitamin K-2 plus vitamin D-3 compared to a vitamin D-3 supplement alone. 

There is no question now: 

1) Supplemental intake of vitamin K-2 is strongly associated with reduced risk and evolutions of cardiovascular disease; and 

2) Vitamin K-2 uniquely reduces bone fracture risk and occurrences AND reduces the development of osteoporosis. 

These findings are evidence-based among many population studies and are well understood at the molecular and tissue level.  

Vitamin K-2 is additive to vitamin D-3 in bone wellness, strength, and integrity. And vitamin K-2 is considered among experts now to be the most effective factor toward prevention and reversing the vascular calcification that is central to progressive atherosclerosis of arteries. 

Food sources of vitamin K2

While vitamin K-1 is found principally in leafy greens and other green vegetables, only certain rarely eaten animal products are a possible food source of vitamin K-2.  Nutrition scientists know that beef and chicken liver, heavily-fatty meats from grass-fed livestock, and egg yolks, but not egg whites are potential food sources of vitamin K-2. Strongly fermented cheeses made with whole milk supply small amounts of Vitamin K-2. For the vegetarian, only Natto-fermented soybeans are food sources of vitamin K-2. Natto is the only vegetarian source of vitamin K2 because of a specific strain of bacteria used in its fermentation process. 

As mentioned already, vitamin K-2 supplementation has become strongly recommended by many National Nutrition Boards worldwide. Vitamin K-2 supplements as capsules are now widely available and these are declared safe up to 150 mcg per day. Important to know, vitamin K-2 does not promote blood clot formation and does not interfere with any prescribed blood-thinners. 

Easily procurable vitamin K-2 supplements typically contain 45-90 mcg per capsule, and once per day is ideal. More than 100 mcg per day is not needed. Health benefits described above appear with intake 50-90 mcg per day. Adjusting food intake to include high amounts of fat-laden meats and liver is not recommended, as the saturated fat intake is not healthy. Fermented soy is healthy. Fermented cheeses are also healthy. But substantial amounts of these foods would have to be eaten almost daily to ingest the adequate amount of vitamin K-2. So, K-2 supplements are wise.

In summary: 

• Vitamins are essential for life and wellness.
• Vitamin deficiencies are widely recognized as causes of illness. 
• Vitamin K-1 and K-2 are essential vitamins, each with unique actions.
• Vitamin K-1 enables blood clot protein production.
• Vitamin K-1 is abundantly supplied in a diet that contains leafy greens and vegetable greens. 
• Vitamin K-2 protects against vascular calcification, and even reverses vascular calcification.  
• Vitamin K-2 enables the transport of calcium into our bones and along with vitamin D-3 facilitates bone construction and bone remodeling.
• Vitamin K-2 also appears to additionally protect and to reverse osteoporosis beyond vitamin D-3 alone.
• Vitamin K-2 is much less abundant in foods. Yes, fatty meats contain K-2, and fermented soy and cheeses also contain K-2. However, the usual dietary intake of K-2 is largely inadequate, and heavily fatted meats are unhealthy.
• So, yes, vitamin K-2 supplements as capsules are a very wise undertaking. Vitamin K-2 supplementation of 45-90 mcg per day will benefit your health in amazingly measurable and positive ways and is not contraindicated in any setting nor adverse in any particular way. 
• And, so, vitamin K-2 has amazing biological synchrony: blocking vascular calcification while promoting bone strength and health.
• Yes, get started. The amazing story of vitamin K-2 and it's very positive and unique impact on vascular and bone health is truly motivational.