Dental tradition teaches us that calcium is the most important nutrient for strong bones and teeth, and it’s the reason school cafeterias across the country serve up milk by the case. Yet calcium, alone, isn’t enough to ensure dental health. It is vitamin K2, working synergistically with calcium and other minerals, that is most responsible for preventing cavities and even reversing some pre-existing cavities.
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Vitamin K2 and Activator X
In 1939, famed dentist Weston A. Price published a body of research that provided a foundation for the future of preventative dental care and, in truth, a guide to optimal health overall. (1)
For years, Price had studied primitive groups around the world that enjoyed long lifespans, minimal disease occurrence, and very few incidences of cavities or gum disease. And this was the case even though those cultures had no exposure to the Western world and its modern “advancements”. Shockingly, many of the people Price documented had never heard of a toothbrush.
Yet one pattern arose in Price’s research: Those cultures commonly ate foods high in a compound that Price had no name for, prompting him to call it “activator X.”
Once Price realized the impact of activator X on dental health, he abandoned nearly all conventional dental procedures in favor of a system of dietary recommendations. And he found that those recommendations led to straight, healthy, cavity-free teeth in most cases.
While we aren’t certain what Activator X was, the best guess within the scientific community is that Price was generally referring to vitamin K2. (More specifically, science leans toward the fact that K2 is most powerful when operating synergistically with vitamins A and D3.)
So what makes vitamin K2 different from vitamin K1?
Well, it wasn’t until 1975 that Harvard researchers realized that vitamin K2 wasn’t just a different version of vitamin K1 with the same benefits. On the contrary, they discovered the protein osteocalcin, which is dependent upon Vitamin K2 for activation. Once activated, osteocalcin pulls calcium from the bloodstream into your bones and teeth to keep them strong and disease-free. (2) Vitamin K1 doesn’t have the ability to activate that process.
With a new focus on vitamin K2 and its specific benefits, it would make sense for doctors and dentists to promote it as a vital nutrient and encourage people to get more of it in their diets. But that just wasn’t the case.
In 2007, 68 years after Price published the incredible benefits of Activator X, researchers finally realized that most people in modern society are deficient in Vitamin K2. (3) The ramifications of this are huge, as scientists believe that vitamin K2 may have the potential to reverse the heart disease and diabetes epidemics.
And, of course, without vitamin K2, it is nearly impossible to achieve optimal oral and dental health.
What most people get wrong about oral and dental health
For years, the focus of oral health has centered around calcium and vitamin D3. Both of these nutrients are important—calcium is the basic building block for our teeth and necessary for reversing cavities naturally. (4) Vitamin D3, meanwhile, is a fat-soluble vitamin that functions somewhat like a hormone. And your body needs D3 in order to balance minerals and absorb the calcium you consume. (5)
Up to 90 percent of the population is deficient in vitamin D, which leads many people to assume that the best way to protect bones and teeth is to increase intake of these nutrients. (6) For example, calcium supplementation has long been a go-to remedy for preventing osteoporosis, which is classically associated with calcium deficiency.
But we’ve learned that supplementing with calcium on its own tends to cause an increase in heart-disease causing plaque. (7) So what’s the problem here? And why is the remedy for one problem causing another, potentially more dangerous one?
The issue is that focusing on calcium by itself can’t achieve desired results, like stronger bones and healthy teeth. Yes, you need vitamin D3 for balance and absorption, but even those two nutrients together don’t provide a complete solution.
Without vitamin K2, the body’s calcium may not end up in bones and teeth where it’s actually needed. Instead, it may travel to arteries where it calcifies and leads to heart disease.
Vitamins D3 and K2 work synergistically to carry and deposit calcium to your teeth and bones where it can be properly absorbed. And when one part of that system is out of whack, the whole process becomes disrupted—which can lead to poor dental health, even when you’re brushing and flossing regularly.
Too little calcium? Your teeth will be subject to faster demineralization, which can lead to cavities. Additionally, calcium deficiency during pregnancy can result in malformed or weakened teeth in the developing fetus. (8) Not getting enough D3? Calcium won’t be properly absorbed, and you can also expect more risk for gum disease (which, by the way, is linked very closely with the development of type 2 diabetes). (9)
And what happens when there’s a vitamin K2 deficiency? To understand the impact, let’s take a closer look at how vitamin K2 works and what it does.
What is vitamin K2?
Like vitamin D3, vitamin K2 is a fat-soluble vitamin. It is produced in small amounts by healthy intestinal bacteria, but it must be primarily gained from the diet, whether via or supplements. And because we are still in the early stages of recognized research on K2 supplementation, there is no recommended daily intake at present.
That said, like naturopathic doctor Kate Rheaume-Bleue, I believe vitamin K2 to be an essential vitamin as much as any other. Rheaume-Bleue succinctly describes the role of vitamin K2 in her book, Vitamin K2 and the Calcium Paradox: (10)
“Vitamin K2 funnels calcium into bones to strengthen mineral density and fight fractures while it prevents and even removes dangerous arterial calcification. Along the way it has beneficial effects for almost every major health concern of our time, including diabetes, cancer, Alzheimer’s disease, infertility, tooth decay, and growing healthy children.”
Vitamin K2 is essential because of the proteins its activates. Although vitamin D transports valuable calcium to the bloodstream, it doesn’t determine where it goes after that. Instead, that responsibility falls on the K2-dependent matrix gla protein (MGP). MGP finds calcium in soft tissues (including arteries and veins), and osteocalcin directs it to teeth and bones.
Various types of vitamin K2 exist, some synthetic and others naturally occurring. Most commonly studied is MK4, a synthetic vitamin K2 compound with a short half-life. That means that when in supplement form, you have to take it three times a day to reap its benefits.
MK7, however, is derived from natto (a Japanese, fermented soy food). It is both a naturally-occurring form of vitamin K2, and it has a longer half-life than MK4. (More on this later). (10)
Vitamin K2 benefits
Here’s a more thorough explanation of the benefits of vitamin K2:
1. Builds New Dentin
Because osteocalcin is a K2-dependent protein, increasing vitamin K2 intake causes osteocalcin to work more efficiently. (11) When osteocalcin is activated by K2, it causes the growth of fresh dentin (calcified tissue that underlies the enamel layer of teeth), and when new dentin grows, cavities are less likely to form. (12, 13) (Note that this process also requires vitamins A and D.) (14)
2. Slows Tooth Degradation
Similarly to how it impacts bones, it is believed that vitamin K2 helps to slow the rate of tooth loss that occurs with age. In fact, when it comes to bone, K2 has been observed to actually increase bone mass. (15)
3. Leads to Normal Facial Structure
One of the most striking findings that Weston A. Price documented during his travels was the difference in face and jaw structure of those exposed to Western diets as compared to those subsisting entirely on a traditional diet. (1)
As Rheaume-Bleue explains, vitamin K2 is extremely important during fetal development. When mothers don’t consume enough of this vitamin, the nasal cartilage of the fetus is calcified too early and can lead to undergrowth of the bottom third of the face. This condition is considered extremely rare and is known as maxillonasal dysplasia or “Binder’s syndrome.” (16)
But while the most advanced stages of this condition are rare, you probably see less severe cases every day. Have you ever noticed a child with teeth that clearly don’t fit in their oral cavity, leading to misshapen or displaced teeth? That’s caused by vitamin K2 deficiency during fetal development.
Price saw it happen to children born to mothers who had previously birthed children with perfect teeth and facial structures. If women were exposed to a K2-deficient Western diet between births, the younger children suffered developmentally. The reverse, however, was also true. Once back on a traditional diet, mothers gave birth to children with properly formed faces and jaws, who were able to grow straight, strong teeth. (1)
The impact of the Western diet on facial development is one reason I believe modern dentistry has had to turn to so many external mechanisms like braces, bridges, and the removal of wisdom teeth. But there is an alternative.
4. Kills Cavity-Causing Bacteria
One key factor in cavity formation is the disruption of the oral microbiome.
The mouth is full of trillions of bacteria at any time, and it’s the healthy bacteria that help to beat bad breath and stop cavities from forming. Unfortunately, it’s very common for bad bacteria to proliferate and crowd the good ones out. When this happens, harmful bacteria can lead to cavities, gum disease, and other issues.
To illustrate the impact of vitamin K2 on the oral microbiome, Price repeatedly conducted a simple experiment. He treated patients with a butter oil very rich in vitamin K2 and found that the cavity-promoting bacteria was decreased by up to 95 percent, sometimes going away altogether. (1)
5. Promotes Overall Health
As I’ve mentioned, vitamin K2 interacts with a vast number of bodily processes. And because what happens in the mouth happens in the body, it’s not surprising to know that vitamin K2 can support total-body health.
Other vitamin K2 benefits that are not related to the oral cavity include:
Heart Disease: To date, vitamin K2 is the only known nutrient that can not only protect from but also reverse plaque buildup in the arteries. (17) This makes it a vastly important part of a heart-healthy diet and supplement plan, provided you also get plenty of vitamin D and calcium.
Osteoporosis: Now that scientists have resolved the “paradox” of supplemental calcium leading to heart disease, they have naturally discovered that K2 plays an important role in the prevention of osteoporosis. vitamin K2 allows the transport of calcium out of the bloodstream and into the bones (10), and more specifically, MK7 seems to be able to counteract the loss of bone density that’s common in menopause. (18)
Alzheimer’s: Even though vitamin K2 doesn’t act like a traditional antioxidant, it has a unique ability to reduce or prevent oxidative stress in the brain. (19) This stress is one of the causes of Alzheimer’s disease, a disease very closely related to bone loss in osteoporosis, as well as insulin resistance in diabetes.
Diabetes: One of the major discoveries in 2007 regarding vitamin K2 involved its impact on insulin sensitivity. Activation of osteocalcin in the bones can actually improve glucose tolerance, suggesting it can help to prevent type 2 diabetes. (20)
Healthy Veins: Although vitamin K1 plays a major role in blood flow, K2 helps to activate MGP, which often collects in varicose veins. By activating this protein, K2 can support the reduction or prevention of varicose veins and related thrombosis problems. (10)
Cancer: People who consume the highest amounts of K2 have a lower risk for all types of cancer. They are also less likely to die from cancer should they contract it. (23) The impact of this has been specifically observed with leukemia, prostate, lung, and liver cancers. (24, 25, 26, 27)
Kidney Disease: Having less-than-optimal K2 and vitamin D levels are associated with a higher risk of kidney disease. (28)
Fertility: Observed both by Price in the 1930s and in more recent research, vitamin K2 impacts fertility (for both men and women) and subsequent labor. (10)
The Difference Between K2 and K1
It’s important to note that the benefits just mentioned are specific to vitamin K2—and that there are major differences between vitamins K2 and K1.
Found in leafy greens like kale, vitamin K1 (phylloquinone) also activates proteins, but the proteins it activates are those responsible for blood clotting. As a result, a common sign of vitamin K1 deficiency is the failure of the blood to clot properly.
Unlike vegetable-based K1, K2 is found primarily in animal fats and natto, which is the only vegan option for K2 consumption.
K1 is converted to K2 via an important enzyme, and it’s one that humans don’t possess. So while humans and animals alike consume K1 for leafy greens, animals are then able to transform the K1 into K2 and reap additional benefits.
Vitamin K2 is produced in a healthy human gut, but the process is much less efficient than that of animals like cows and chickens. This explains why getting vitamin K2 from animal sources is best, as they’ve done the converting for us.
K2 Deficiency Signs and Symptoms
Unlike those of vitamin K1, signs and symptoms of a K2 deficiency are often harder to spot. A K2 deficiency is also difficult for a doctor to detect, as K2-specific blood tests aren’t available in most medical practices.
That said, you may be deficient in vitamin K2 if you: (29)
- Are vegan and don’t eat natto
- Experience plaque buildup in arteries
- Develop kidney stones
- Frequently get cavities
- Are insulin resistant
- Have varicose veins
How to get more K2
The best way to get more vitamin K2 is through your diet. In 3.5-ounce portions, the highest vitamin K2 foods are: (10)
- Natto—1103.4 micrograms
- Goose liver pate—369 micrograms
- Hard cheeses—76.3 micrograms
- Soft cheeses—56.5 micrograms
- Goose leg—31 micrograms
- Egg yolk—15.5 micrograms
- Butter—15 micrograms
- Chicken liver (raw)—14.1 micrograms
- Chicken liver (pan-fried)—12.6 micrograms
- Cheddar cheese—10.2 micrograms
Depending on the availability of these foods (and your willingness to acquire the unique taste of natto), you may also consider taking a vitamin K2 supplement. I would recommend this particularly to those at risk of the diseases impacted by K2, as well as anyone unable to eat foods like the ones listed above.
As I mentioned, there are two forms of K2 available in supplement form. I will always suggest sticking with MK7 over MK4, as MK7 only has to be taken once a day and can be taken in much smaller quantities than its counterpart. Additionally, MK4 is easily found in eggs, while MK7 is more difficult to source from food.
Vitamin K2 dosage should be somewhere between 90-120 micrograms daily in MK7 form for most adults. There is no upper limit of vitamin K2 known to be toxic (unlike the other fat-soluble vitamins), so that number is a general rule but can be exceeded safely.
Children generally shouldn’t need as high of a dose because they’re physically smaller, so I would stick to around 45-50 micrograms daily for kids.
More good news exists for people on medications like warfarin, who typically have to avoid vitamin K foods. Unlike vitamin K1, K2 isn’t necessary to avoid when taking blood thinners. In fact, taking up to 50 micrograms of vitamin K2 in MK7 form counteracts the medication’s side effects without stopping it from working properly. (30)
Final Thoughts on K2
Originally discovered in 1939 by dentist Weston A. Price but only recognized in much later years as the important nutrient it is, K2 is a form of vitamin K that plays an essential role in dental health, bone formation, and the prevention of heart disease and other conditions.
In 2007, a study was published that determined most people in modern society are deficient in K2. This has a massive impact on oral health, as vitamin K can help to build new dentin, slow tooth degradation, lead to more normal facial and jaw structure, and kill cavity-causing bacteria.
Vitamin K2 is produced naturally in the gut—but the process isn’t extremely efficient, especially when the gut isn’t healthy. As a result, K2 must be primarily gained from diet. So to increase your intake, try K2-rich foods like natto (the only vegan option), goose liver pate, hard and soft cheeses, goose leg, egg yolks, butter, chicken liver and cheddar cheese.
Although it’s a fat-soluble vitamin, there is no upper limit of safety for vitamin K2 supplements. I typically recommend 90-120 micrograms daily for people who may be deficient in K2.
It’s also important to reiterate that we are not 100% certain that Weston Price’s Activator X is vitamin K2. We do understand the benefits of vitamin K2, which is why I highly recommend adding more of it to your diet. But I also advise consuming a balanced diet that is rich in other nutrients as well, including vitamins D3 and A, and minerals like calcium and magnesium.
Who knows—they may have been part of the Activator X as well.Read Next: Top Vitamin K2 Foods for Healthy Teeth