Until quite recently (c. a decade), the function of vitamin K (a fat-soluble vitamin, as are vitamins A and D) was thought to be related to blood-clotting (coagulation).

But according to more recent scientific research findings, vitamin K (particularly in the form of vitamin K2) is connected to

  1. the regulation of calcium distribution (i.e. how our body uses and stores calcium) via the activation of certain proteins which deposit and organize calcium and phosphorus in bones and teeth and thus keep that same calcium from being deposited in the soft tissues of blood vessels, kidneys etc.
  2. the synthesis of certain lipids (the nerve cells' myelin sheath) used in the metabolism of our brain

The above important functions will be properly carried out with an adequate supply of vitamin k2 while insufficient intake contributes to both bone and vascular problems (abnormal calcification or accumulation of atherosclerotic plaque in heart and kidney [stones][6], vascular inflammation etc.).

Vitamin K exists in two main forms, K1 and K2. While due to their structural and chemical resemblance, the two K vitamins are classed in the same family, studies point to them not being interchangeable.[1]

Our body seems to "prefer" using vitamin K1 for activating blood clotting proteins in the liver, and vitamin K2 for the above-listed functions (i.e. placing calcium in our bones and teeth [where it is required for health] while preventing it from landing in the soft tissues (where it can and often does do harm such as creating cardiovascular disease).

To make matters somewhat more complex, the K2 vitamins also form their own family of slightly differing forms, the so-called menaquinones. The ones of most interest to our discussion are menaquinone-4 (MK-4) and menaquinone-7 (MK-7) since these constitute the two principal sources of natural vitamin K 2 in our diet (so we will disregard here other forms such as MK-8, MK-9, MK-10, 11 etc.).

Dietary (food) sources of vitamin K1 and vitamin K2 (menaquinone-4 [MK-4] & menaquinone-7 [MK-7])

Vitamin K1 can be found in many green and/or leafy plants and vegetables (such as spinach, lettuce, broccoli, avocados, chard, cruciferous vegetables like brussels sprouts, cabbage etc., spirulina [blue-green microalgae], freshly grown wheat grass and alfalfa, other rapidly growing green plants, green tea, etc.).

Vitamin K2 is found in fats from grass-fed animals and in fermented foodstuffs, the latter of both plant[2] and animal origin (cheeses, yoghurt and other fermented dairy products).

Animal fats/products contain the vitamin K2 form known as MK-4 while fermented foods contain the MK-7 form made by lactic acid bacterial fermentation. It is presently not known which of these forms is more efficient.

Natto, a fermented soybean product popular in parts of Japan[3], seems to boast the highest amount of vitamin K2 (which since it derives from fermentation is present in the form of menaquinone-7 [MK-7]).

One table for instance states the MK-7 content of 100 g of Natto as a whopping 1,100+ mcg while 100 g of hard cheese are listed as containing c. 76 mcg (with 6% existing in the MK-4 form) and 100 g of sauerkraut as only c. 5 mcg.

This is good news for vegetarians and vegans which can thus have a tooth-friendly diet containing an abundance of vitamin K2 (without having to resort to animal foods) by consuming natto (or at least plenty and plenty of fermented foods) or simplest, using vitamin k2 supplements derived from natto.

Various sources also include a mention of the human body's intestinal flora producing vitamin K2 from K1 but the extent of this conversion presently appears to be unknown.

Special note re spirulina

As a green “superfood” supplement, spirulina is rich in vitamin K1 but may not contain any Vitamin K2. However, one company called Cyanotech recently announced that "an independent contract laboratory” had discovered c. 15 mcg of vitamin K2 per 3 gram serving in its Hawaiian Spirulina Pacifica product. So some green supplements may be a valid plant source of K2.

K2 & the health of your teeth:
vitamin K2 is Dr. Price's cavity reverser 'Activator X'

For an introduction to eminent dentist and researcher Dr. Weston A. Price's work, see Dr. Weston A. Price's research into diet and dental health and disease.

Later in his scientific career, Dr. Price discovered a nutrient which showed dramatic curative benefit for his dental patients when administered in combination with high-vitamin cod liver oil and a nutritious diet (containing items such as whole milk and unprocessed grains, fruits and vegetables, organ meats etc.).

This key nutritious substance was detected in vitamin-rich butter and butter oil concentrate extracted from it. Finding himself unable to determine its exact nature and chemical identity, Dr. Price termed it "Activator X"[4].

Using high-Activator-X butter as the key element of his dietary anti-cavity protocol, Dr. Price was able to stop tooth decay in its tracks and completely reverse it. Previously active cavities started to grow new dentin and remineralize, glazing the formerly carious tooth with a new finish and making all dental work superfluous.

One dramatic case history involved a 14-year-old girl who after taking Activator X concentrate and high-vitamin cod liver oil capsules three times daily during the space of seven months experienced the complete healing of the whopping 42 cavities she had in 24 teeth.

Price found great variations in the Activator X concentration among butters from various sources. Butter made from the milk of cows grazing on vitamin-K-rich pastures (particularly rapidly growing wheat grass and alfalfa) yielded the highest amounts of Activator X.

The soil quality also strongly influenced Activator X concentrations (interestingly and in line with other observations regarding the nutritional quality of foods grown on rich vs. depleted soils, Activator X concentrations in butter were found to be lowest in US-American states with the longest history of agricultural use of its soils [the East and the Far West], while they were shown to be highest in Deaf Smith County (Texas), the very county dentist George W. Heard found to be "free of toothache" (see A dentist who proved the vital importance of mineral-rich nutrition to dental health).

As has now been virtually established, the sought-for true identity of Price's Activator X is vitamin K2. All the characteristics Dr. Price detected in Activator X are indeed exhibited by vitamin K2. Here are some of the facts Dr. Price discovered:

  • Activator X is synthesized by animals from a precursor found in rapidly growing grass. (Vitamin K2 is synthesized from vitamin K1 found in green plants.)
  • Activator X is found in the fatty portions of milk and in animal organs and fats (so is vitamin K2).
  • Activator X acts in synergy with vitamin A and vitamin D. (Vitamins A and D signal cells to make proteins such as osteocalcin, vitamin K2 subsequently activates these proteins.)
  • Activator X plays a crucial part in the utilization of minerals and is a required element for the control of tooth decay. (Vitamin K2 activates the proteins which deposit and organize calcium and phosphorus in bones and teeth and keeps that same calcium from being deposited in the soft tissues of blood vessels, kidneys etc.)
  • The intake of Activator X is inversely related to the incidence of heart disease. (Vitamin K2 helps prevent abnormal calcification or accumulation of atherosclerotic plaque in the heart and kidneys, blood vessel inflammation etc. by maintaining calcium in the bones and discouraging calcium deposits from forming in arteries.)

Supplementing with vitamin K2

There are two types of vitamin K2 supplements available, one is synthetic vitamin K2 (menaquinone-4 or MK-4) and the other is natural MK-7 (menaquinone-7) derived from natto.

Synthetic MK-4 is considered equivalent to the natural vitamin K2 (MK-4) present in animal fats and has been used in osteoporosis studies performed in Japan which established the link between K2 and bone health as well as in the majority of animal experiments[5] performed with similar purposes.

When taking vitamin K2 in pill form, you may wish to combine its ingestion with fat since this has been found to increase its uptake by the body ("bioavailability"). No toxic effects have been observed from high doses of vitamin K2.

While some sources maintain that menaquinone-7 is light-sensitive I could only confirm this for vitamin K1 (destroyed by sunlight after one hour) and for menaquinone-4 ("decomposed by light"[7]). It should do no harm however (and possibly be wise) to also store one's natural MK-7 K2 supplement in a dark place.

A look on the internet shows that there are numerous sellers offering various vitamin K2 supplements of various qualities. If you go for supplementation, choose wisely :-).

Note: It goes without saying that vitamin D is essential to dental (and other) health as well, as is vitamin A, C, etc. Make sure you have sufficient levels of all essential nutrients.

Caveat: patients taking oral anticoagulants (warfarin and the like) should ask their physician before taking vitamin K2 supplements since the latter interfere with the former's activity.

Just be aware that vitamin K antagonists (coumadin/warfarin...) increase your risk of arterial and heart valve calcification and that there are numerous natural substances that help to thin blood (from vitamin E to flaxoil/cottage cheese[8] and many herbs and spices in-between, not to mention what will be sometimes forgotten - properly hydrating yourself by drinking enough water).

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1 For example, only vitamin K2 has been found to be linked to a lower risk of heart disease. The so-called "Rotterdam Study" found that high vitamin K2 intake lowered the risk of serious arterial calcification by 52 % and mortality from cardiac disease by 57 %, while a high vitamin K1 intake showed no effect.

2 Cultured vegetables such as the well-known sauerkraut. Perhaps unknown to many, virtually any plant can be fermented (subjecting perishable foods to bacterial fermentation was one of the main processes our ancestors used to preserve food).

3 but not elsewhere due to its strong taste

4 Activator X is also referred to as X-Factor or Price factor.

5 Healing Teeth Naturally does not endorse animal experimentation, for the reasons compare for instance Animal Experimentation Unscientific.

6 ... and judging by one anecdotal report I have come across so far, vitamin K2 may also help to heal (remove) dental plaque which in its later-stage calcified form called calculus or tartar indeed contains calcium (see case report Dietary change [no grains]).

7 https://monographs.iarc.fr/ENG/Monographs/vol76/mono76-16.pdf

8 Center part of the Budwig diet.

All Healing Teeth Naturally articles on nutrition and dental health