In fact, I'm not just talking about vitamin K, but about vitamin K2.
"Vitamin K2? Really?"
I get where you're coming from...
You might know about vitamin C, and vitamin D3 if you're really into health.
But vitamin K2?
That latter vitamin is very important...
In fact, I'm assuming that this vitamin will be considered just as important as the other ones over time. When important Vitamin K2 studies came out fifteen years ago, almost no-one knew about this substance.
Times are changing slowly.
As of today, still very few people know about vitamin K2's importance as well.
My goal is to change that.
In this article, you'll learn about vitamin K2's benefits, and how to optimally consume it through your food. I'll also tell you about vitamin K2 deficiency, and possible supplements.
If you have problems with your bones, teeth, or if you have heart disease or diabetes, this blog post is especially recommended to you.
Vitamin K2 is found in eggs, (organ) meats, cheese, butter, and fermented soybeans. Vitamin K1 is plant-based and does not have vitamin K2's health benefits.
You probably know that you need vitamin D and magnesium for optimal health.
What you might not know that vitamin K2 is equally essential for your health.
Let's first look at vitamin K2's history.
In the 1930s and 40s, the now-famous dentist Weston A. Price assumed that there was a health-promoting substance contained in milk, butter eggs, and organ meats.
Price could not identify that substance as vitamin K2 though.
Price called that substance "activator X" instead.
He did not specifically know which specific substance in milk, butter, eggs, and organ meats caused these health benefits.
Price thus remained in the dark what activator X really was.
What he did know, is that activator X helps prevent heart disease, protects against tooth decay, aids in reproductive function, and increases cognitive functioning.
Price argued that many traditional cultures had diets that were very high in activator X. According to him, the Western diet had become a poor source of activator X back then.
Keep in mind that Price made this conclusion about the Western diet in the 1930s and 1940s. Imagine what he would conclude today.
Price learned about activator X by studying the health and dietary habits of traditional cultures. One culture he observed were the Maasai in Africa:
Price concluded that traditional cultures - such as the Maasai - did not have any heart disease or tooth decay.
In the West, tooth decay was already rampant - heart disease started to emerge too.
Activator X remained a mystery during Price lifetime, and many decades afterward.
Price never identified activator X as vitamin K2 - which were later found to be the same substance.
Remarkably, methods were already developed to detect vitamin K2 during the 1970's.[3; 4; 6; 7; 43] Back then, vitamin K2 was falsely assumed to have the same properties as vitamin K1. For that reason, scientists did not really have a closer look at vitamin K2.
It was falsely believed that vitamin K2 had few consequences for your health - as vitamin K1 did.
In the 1990s, things changed. The health consequences of vitamin K2 were discovered, and separated from vitamin K1.[44; 45]
In 2007, it was finally demonstrated that vitamin K2 and activator X are the same compounds.
Why does that matter for you?
Vitamin K2 will allow you to reap some of the health benefits that these traditional cultures experienced.
In this article, I'll first tell you about my background with vitamin K2. I'll subsequently give you the best vitamin K2 food and supplements. Lastly, you'll learn how to avoid deficiencies in this vitamin.
As it turns out, if your goal is optimal health, not all vitamin K2 food sources and supplements are created equal.
This article concludes that getting vitamin K2 through either foods or supplements is absolutely necessary if your goal is optimal health.
For your convenience, I've included a summary at the beginning of this article.
If you just want to understand the vitamin K2 basics, read the summary section. If you want to understand all the details, read this entire article.
Note: this blog post - like my previous blog posts - contains some nerd sections. These nerd sections contain more advanced explanations. You can skip these nerd sections if you just want to understand the basics about vitamin K.
Let's start learning about this fascinating vitamin...
Chris Masterjohn, who originally posited that vitamin K2 equals Price's Activator X, now argues they are not the same substance. Nevertheless, due to vitamin K2's already proven effects in high-quality studies in the last few decades, I presume that both substances may actually be beneficial. The true nature of "activator X" has thus yet to be discovered. Click here for more information.
Not all vitamin K is of equal value. There are two main types of vitamin K:
It's pretty easy to consume sufficient amounts of vitamin K1 through your diet. Vitamin K1 does not have all the benefits of vitamin K2 though.
If your goal is optimal health, you need to include vitamin K2 sources in your diet.
The best vitamin K2 sources come from cows, geese, ducks, chickens, that are pasture-raised or 100% grass-fed. If these animals are mainly fed grains or corn, their vitamin K2 content is low - which also holds true for any foods that originate from them (cheese; milk; eggs).
So, eating loads of eggs from caged chickens, or grain-fed meats will not get your vitamin K2 needs met.
What to do?
Change your dietary habits. If you don't want to change your diet - or can't (yet) - then supplement.
You'll want to be wary, however, of just supplementing with vitamin K2.
The A; D; E; and K vitamins mutually reinforce each others' actions (if you take normal dosages).
if you supplement with vitamin K2, that usually means that you should supplement with vitamin A and E as well.
What about vitamin D?
If possible, you should get vitamin D from sunlight. Regarding supplements, you can get high-quality versions here:
I know you're wondering:
Why take vitamin K2 in the first place?
Contrary to vitamin K1 - which mainly helps with coagulation - vitamin K2 gives you a host of benefits. Vitamin K2's benefits extend to helping you avoid heart disease, stopping and reversing tooth decay, increasing your bone health, aiding your cognition, and increasing your hormonal function.
Vitamin K2 has enormous overall health benefits.
That's why it's very sad that the importance of vitamin K2 is really underappreciated in our society. Most people are deficient in vitamin K2 - even apparently healthy people.
While more research is needed, I do think that it's essential to get enough vitamin K2 in your diet. And if you do not get enough vitamin K2 in your diet, you need to supplement.
You can view the most important vitamin K facts here:
And yes, you can share that infographic (I know reason 10 is missing!)
And of course:
Continue reading the full vitamin K story...
I've gotten lucky.
For many years, I had been consuming tons of vitamin K through my food by accident. I didn't really get into studying vitamin K until I was already occupied with health for 10 years.
Why did I consume lots of this specific vitamin by accident?
I have been lifting weights since 17 years of age. I'm 31 right now. During that period, I've always included food sources that turned out to be great vitamin K sources.
I trained a lot. I had been eating tons of food to gain muscle.
What (crazy) things did I do?
As it turns out, there were all great vitamin K sources.
(before you ask: why did I drink the raw eggs? Because drinking them was very time efficient - you could ingest tons of protein within just a few minutes.)
Yes, I know that sounds weird to most people.
As I grew older, I started to eat more and more vegetables that were deemed very high in vitamin K. Kale and spinach are examples of such vegetables.
At the same time, I consumed a ton of eggs, fish, and (organ) meat.
Should I have had very high vitamin K levels right? I thought so...
But when I finally tried a high-quality vitamin K supplement, I got additional benefits.
Was that result not supposed to happen?
I should not have gotten any benefits at all. My vitamin K levels should have already been very high.
What exact benefits did I experience?
Do I have any hard proof of vitamin K having this effect?
Some people swear my facial and jaw structure have changed. Compare these two photographs, for example.
The first is from 2015 - two years before I took a vitamin K2 supplement:
The second picture is from 2018:
Judge for yourself...
Keep in mind that I'm not the only one who reported these results. Many vitamin K2 users report changes to their facial structure over time.
These results left me at a dead end. Should you supplement with vitamin K or not? And under what circumstances should you supplement?
I decided to dig into the research. I left no stone unturned.
Stay with me to find out what happened.
Let's first look at the different types of Vitamin K.
Vitamin K1 was already discovered during the 1930's. The vitamin was correctly identified as playing a major role in blood clotting.[38; 39; 40; 41]
The specific functions of Vitamin K2 only became known during the 1990's. Vitamin K2 signifies thus somewhat of an unexplored terrain in science.
What are the differences between vitamin K1 and vitamin K2?
Vitamin K1, firstly, is mainly found in green vegetable plants. Take a look at the top-10 list of foods high in vitamin K1:
All these foods are measured per cup.
Pick your favorite
vitamin K1 food.
Your body converts vitamin K1 into vitamin K2. Contrary to other animals, however, humans do not convert K1 into K2 very efficiently. More on that conversion later.
Let's take a look at vitamin K2 first.
Large quantities of vitamin K2 are only found in animal foods.
How do animals create the vitamin K2 you consume?
When eating grass, these animals convert K1 into K2:
One of nature's best
K1 to K2 conversion "machines"...
Other animals - such as chickens - may accumulate vitamin K2 through the worms and insects they consume.
That vitamin K2 is subsequently stored in the animal's body.
You consume that vitamin K2, by eating these animals, or the products that come from them (eggs; milk; cheese).
Let's look at why you can't you rely on vitamin K1.
Only some vitamin K1 can be converted into K2 by your human gut.[55; 111-112]
You cannot fully rely on that conversion. First of all, it's not yet known how well human beings convert vitamin K1 to K2. And secondly, human beings who rely on the conversion of vitamin K1 into vitamin K2 end up with a vitamin K2 deficiency.
But there's another reason to consume vitamin K2.
Vitamin K1 and vitamin K2 have totally different effects in your body.
You can compare the different effects of vitamin K1 and K2 to the very different effects that vitamin D2 and D3 have. Vitamin D2 is a plant version, which does not have the same health benefits of vitamin D3.[54; 55; 69]
Why does this matter for you?
Vitamin K2 has many, many benefits for your health.
Vitamin K2 improves bone health, helps prevent heart disease, keeps your joints healthy, promotes preventing diabetes and Alzheimer, and enhances your hormonal and organ function.
Here's a more elaborate display of vitamin K2's benefits.
As you can conclude yourself, vitamin K2 is very important for your health.
So, let's find out how you can get adequate vitamin K2 from your food.
You might be asking: "don't I get enough vitamin K through the foods I consume?"
Stay with me to find out why.
Remember that greens were the best vitamin K1 sources and that the human body does not convert vitamin K1 into K2 very well. You should not rely on that conversion, because you cannot be certain whether you get enough vitamin K2 that your body can use.
You should thus consume vitamin K2 through your diet.
This is where things go bad for most people.
Let's consider what foods have almost non-existent levels of vitamin K2:
In short, all the foods that many people commonly consume.
So, what's the solution?
Consume foods that are higher in vitamin K2.
But before I give you a list of vitamin K2 foods, let's first look at different types of vitamin K2.
Vitamin K2 is divided into the MK4 to MK11 types.[61; 62; 70; 71]
So there's vitamin K2 MK4, vitamin K2 MK5, vitamin K2 MK6, etcetera.
Don't be frightened. The story is simpler than it seems.
It's important to remember that vitamin K2 MK4 is the most essential type. Your body converts all other types of vitamin K2 into vitamin K2 MK4.
Let's thus consider vitamin K2 MK4 food sources first.
The most common sources of MK4 - per 100g product - are*:
(* Some numbers are averaged, when two food sources were almost the same).
You get the idea: vitamin K2 MK4 is found only in traditional animal foods.
It's important to notice that this vitamin is missing in fish and shellfish.
Next, there are the food sources that contain mainly MK5 - MK11.[61; 62; 72]
MK5-11 are fermented forms of vitamin K2. In the following list, I've added the foods' MK5 - MK11 levels with each other:
Observe that natto and cheese are by far the best K2 MK5-11 choices. Natto is a Japanese fermented soybean dish (warning: the taste!)
(For a more extensive list of vitamin K2 foods - of both MK4 and other types - click here).
I do, however, consider the MK5 - MK11 types of vitamin K2 inferior. I mainly advise getting vitamin K2 from MK4 sources.
Let's now consider how much vitamin K2 you should consume.
That's where the bad news begins.
The daily requirement of vitamin K2 might be as high as 100 mcg, with an optimal dosage of 200 mcg.[37; 126]
"That's impossible" is probably your reaction.
I'll be honest.
This outcome surprised me as well when I was doing all the vitamin K2 research.
Well, you would have to eat 40 eggs - equalling a kilo of egg yolks - to get your K2 requirements met. Alternatively, you would need to consume almost a pound of cheese per day. Or get in some natto every day...
Even more surprising is that this dose needs to be increased to 360 mcg when you're taking vitamin K2 for heart health.
I asked myself: "how and why did we end up this way?" - "why is it so hard to consume enough vitamin K2?
The answer is simple.
Since about 100 years ago, our animals are no longer grazing on pasture.
Take cows for example. Most cows are currently fed grains and corn, which they've never ever consumed during their entire evolution:
100 years ago, however, cows lived like this:
Why did this transition happen?
Food became industrialized. Petroleum and the mass production of corn and grains made modern feedlots possible.[61; 74] Those feedlots ensure that cows no longer graze on pasture. And you already know that pasture is necessary for the conversion of vitamin K1 into K2.
Now you should begin to see why vitamin K2 MK4 is deficient from our modern diet.
To restate the argument:
But: most of today's animals are no longer grazing on pasture.
Animal foods thus end up with low vitamin K2 levels.
You see, the more hours cows spend grazing on grass, the more vitamin K2 they create. The same is true for vitamins A and E, and other nutrients.
But how do you know if animals are high in vitamin K2? How to look for animal fats that are high in vitamin K2?
High vitamin K2 animal fats are much more yellow than their grain and corn fed counterparts:
For cows, full 100% grass-fed beef will give you the best results.
Horses, or bison, should be raised 100% on grass too if you consume these animals. In a similar sense, pastured chicken, geese, ducks, and pigs are nutritionally superior to their feedlot counterparts.
Additionally, look for orange egg yolks. Compare these two yolks, for example:
The yolk on the right is probably higher in vitamin A and K2.
These visual tests are not 100% accurate, however. Chickens are sometimes fed specific foods to darken the color of the yolk.
The best way to know for sure whether your food has really seen pasture is to ask your butcher - or better: buy your vitamin K2 rich food locally.
If you buy 100% grass-fed meats from your local farmer, you can be pretty sure that the food really is high in vitamin K2.
You might be asking now: "can I get too much vitamin K2 as well?"
Extremely high doses of vitamin K2 have been tested without any side-effects. To achieve those dosages through food consumption, you would have to eat 300 kilograms (~660 pounds) of goose leg every single day. Or, you would have to consume 10.000 egg yolks in a day.
And even at these food intakes, there's no overdose. Vitamin K2 is very, very safe.
Next, let's look at the opposite of an overdose: deficiency.
You now know that vitamin K2 is important for your health.
What you probably did not know is that many people are actually deficient in vitamin K2.
Even worse: common government recommendations for vitamin K2 are too low. Vitamin K2 deficiencies are also under-diagnosed.
In addition, if you have a condition, your vitamin K2 needs are much higher.
100 mcg of vitamin K2 is not enough if you have diabetes or heart disease. 500mcg is a better dosage, in those instances.
The combination of these facts ensures that many people are low in vitamin K2 in today's society. People who are considered "healthy" might thus be low on vitamin K2 as well. Vitamin K2 deficiency is thus pandemic, in the same way that vitamin D3 deficiencies are.
Let's be clear...
I'm not fear-mongering here. In fact, I hate fear-mongering.
What I do believe in, on the contrary, is accepting facts--instead of ignoring problems that are developing. If I act like there's no problem with vitamin K2 levels that people have, they will get hurt.
So, I tell the truth.
The truth is that most people need more vitamin K2.
To get their daily vitamin K2. needs met, many people thus have to change their diets or supplement.
You might need to change things too...
We've treated foods. Let's now consider supplements.
What's important in choosing vitamin K2 supplements?
Why do you need to deal with a K2 deficiency proactively?
Sometimes you'll only find out about a vitamin K2 deficiency once it's too late.[66; 67] Heart attacks are an example. You might not experience any symptoms before a heart attack. That's why heart attacks are often called a "silent killer". And yet, vitamin K2 can help prevent this pathology.
But there's an even bigger problem.
You won't even notice that you're vitamin K2 deficient.
Dental problems, heart disease, or breaking a bone, are signs that you're vitamin K2 deficient. Without such obvious instances, however, there are no immediate signs for vitamin K2 deficiency.
So, what's the solution?
The best test for vitamin K2 deficiency is currently your diet:
Do you consume copious amounts of butter, eggs, (organ) meat, cheese, all coming from grass-fed or pastured food sources?
Then you're probably vitamin K2 deficient.
Fortunately, accurate vitamin K2 lab tests are being developed as we speak.
It's not simple to develop a vitamin K2 lab test, because the vitamin is not circulated through your bloodstream as vitamin D is.
Just taking in a lot of vitamin K2 is not enough to achieve optimal health though.
In addition to taking in vitamin K2, you'll also need enough vitamin A and D to properly absorb vitamin K2.
You should never supplement with just vitamin K2, without also knowing what your general vitamin A and D intakes are.
For example, taking very high doses of vitamin D3 (which I do not recommend) will increase your body's demand for vitamin A.
Alternatively, vitamin K2 is useless without your body having the right vitamin A and D levels. And surprise, surprise: sub-optimal vitamin A and D levels are also widespread, even in developed nations.[98; 99; 100; 101]
In the end, there's no simple solution to improving the vitamin K2 levels in your body.
Supplementing is complicated. Eating the foods that you were made to eat as a species, is less complicated.
For your convenience, I've still included the following links to high-quality vitamin A, vitamin E, and vitamin K supplements.
Note that vitamin K2 is expensive, but one bottle can last you for several years. Keep the bottle out of (sun)light.
All are best taken with meals.
But the best solution: change your breakfast and other meals:
Or your lunch and dinner...
Remember: in nature, foods that are high in vitamin K2, are also high in vitamin A, and higher in vitamin E.
Nature is always already balanced. It's harder to go wrong with nature's solutions.
After reading this article, many of you might think: "I'll just take some supplements anyway, and continue eating the food I'm eating."
In this section, I'll argue why that strategy is not optimal.
There's a big presupposition that underlies the strategy to out-supplement nutritional deficiencies.
That presupposition is that you're really ingesting all the nutrients you need through supplementation.
If you look historically, however, supplementation often does not lead to the best outcomes...
What are some examples?
In 2005, supplementing with high doses of vitamin E turned out to increased rather than decreased your overall risk of dying.
That's dying independent of cause...
In hindsight, the risk of death might have increased because of supplementing with just one form of vitamin E, instead of a full-spectrum.
Another example is that right now, we're also finding that our 10 year-long craze with supplementing vitamin D is short-sighted.
Instead of needing just vitamin D, you also need vitamin K2, magnesium, and many other nutrients to get the protective results you want.
What's my point?
By just relying on vitamin K2 supplements, you will be missing out on many important nutrients.
What nutrients? The nutrients in butter, (organ) meat, cheese, eggs, and fermented foods.
Rule: don't try to out-supplement a bad diet.
Vitamin K2 is a very, very important nutrient.
If you're not eating a diet that contains a lot of butter, cheese, eggs, and (organ) meats, you're probably vitamin K2 deficient.
The vitamin K2 foods you consume have to come from grass-fed or pasture-raised animal sources.
What to do about that vitamin K2 deficiency? The best solution is to change your diet. The second-best solution is to supplement it.
If possible, opt for vitamin K2 MK4. The MK4 vitamin K2 type is the ancestral type that we have been consuming before the agricultural revolution.
Accurate vitamin K2 lab tests are hard to find.
Moreover, vitamin K2 supplements are not that expensive on a yearly basis.
If you're spending hundreds of dollars on dental care each year, a $40 yearly vitamin K2 supplement will be a godsend.
Vitamin K2 can thus lower your overall health care costs.
Oh, by the way, you might be wondering about the question that I posed in the introduction:
Why did I experience additional benefits of vitamin K2, when I started supplementing? The reason is simple. Most of my life, I had not been eating pastured sources of milk, eggs, and meat. Even I consumed large quantities of these foods, I was thus still vitamin K2 deficient.
That problem is solved now...
One last thing: beware of websites that promote vitamin K1.
I'm not going to give you names, but many websites promote vegetables or vitamin K1 supplements, while not promoting vitamin K2 specifically.
That's a big mistake.
I hope you now know that vitamin K1 consumption does not have the benefits of vitamin K2.
"How do I make sure my vitamin K2 supplement does not lower my vitamin A, D, or E levels?"
Make sure your supplementation regimen is balanced. How?
First of all, determine if you need to supplement in the first place. If you eat copious amounts of butter, (organ) meats, eggs, and cheese - coming from grass-fed or pastured animals - then there is little reason to supplement.
If, however, you do not consume these foods, then make sure always to combine vitamin A, E, and K supplements.
Which brings us to our second point. Which supplements should you take?
The following links display high-quality vitamin A, vitamin E, and vitamin K supplements.
Note that vitamin K is expensive, but one bottle can last you for several years. Keep the bottle out of (sun)light.
All should be taken with meals.
I do not think that you should supplement with vitamin D, if possible. Read my article that explains why here.
If possible, do not take vitamin A, E, or K by themselves. The vitamins' functions mutually reinforce each others' actions.
(Nerd section: Do not supplement with plant sources of vitamin A, such as beta-carotene, or just one type of vitamin A, such as alpha-tocopherol. These supplements are unbalanced. Your vitamin A should be in the retinol form.[102; 103] Your vitamin E should combine alpha-tocopherol, beta-tocopherol, gamma-tocopherol, and delta-tocopherol. If possible, the vitamin E supplement should be high in gamma-tocopherol - which is exactly why I recommend the vitamin E product listed above).
"When do I have increased vitamin K needs?"
There are several instances when you will have increased vitamin K needs.
First of all, if you have Alzheimers, osteoporosis, heart disease, or tooth problems, then you have increased vitamin K2 needs. Additionally, gut problems - such as a gastric bypass or celiac disease - increase your vitamin K2 needs as well. Kidney problems are the same.
Some medicines, such as statins, increase your vitamin K2 demands.
Lastly, if you're of older age, or if you're breastfeeding, you're also in need of more vitamin K2. The same is true for young people: your needs will be higher as well (young people should look at the next question).
As the article explains, vitamin K1 will not help these problems--vitamin K1's main role is anticoagulation. You need vitamin K2.
"What are my vitamin K needs if I'm a kid or adolescent?"
Many sources report that vitamin K needs are less in adolescents. I believe, however, that vitamin K2 needs are much higher if you're young, or a teenager.
Because you're building your skeleton at that age. There's proof as well. Dental problems, for example - which are highly related to vitamin K2 consumption - and peak around the teenage years.
Once you're 25 or 35, you'll generally have fewer dental problems, and your vitamin K2 needs drop off as well.
"Where is vitamin K stored?"
Vitamin K is a fat-soluble vitamin. Fat-soluble means it's stored in your body-fat.
Contrary to vitamin D, vitamin K cannot yet accurately be measured in your blood. Additionally, vitamin K is found in your heart, liver, and brain, among others.[108; 109]
"Are there instances where taking vitamin K2 is dangerous?"
If you take blood thinners (anticoagulants). These medicines have the opposite effect of vitamin K1.
Consult your doctor before starting in a vitamin K2 regimen.
In all other instances, there have been no reported overdoses of vitamin K2. Vitamin K2 is safe at extremely high dosages, and there's no known toxicity.
This is a post by Bart Wolbers. Bart finished degrees in Physical Therapy (B), Philosophy (BA and MA), Philosophy of Science and Technology (MS - Cum Laude), and Clinical Health Science (MS), and is currently a health consultant at Alexfergus.com.
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