Most people are aware that vitamins are important for general physical and mental health. However, only a few are aware of which vitamins have which effects and what they are responsible for. This also applies to one of the most important vitamins for us humans, vitamin K2.
In this article you will find out what effect vitamin K2 has. We have compiled and explained the most important functions that have been found through scientific studies. So if you want to know how vitamin K2 works in the body and what tasks it has, you've come to the right place.
the essentials in brief
- Vitamin K2 usually works indirectly by activating proteins that are responsible for vital processes through chemical reactions.
- In this way, vitamin K2 plays an important role in blood clotting, strengthening our bones and preventing calcium deposits in the blood vessels.
- Vitamin K2 can also be helpful for diabetes because it makes the body react more sensitively to insulin. Some studies even indicate an effect of vitamin K2 against cancer tumors.
Background: What you should know about the effects of vitamin K2
In order to clarify how vitamin K2 works, we first want to classify the vitamin more precisely. The individual functions are then discussed in the following paragraphs.
What is vitamin K2?
Vitamin K2 (or menaquinone) is one of two natural vitamins that belong to the group of K vitamins. Just like vitamins A, D and E, vitamin K belongs to the group of fat-soluble vitamins. This means it can be stored by the body, at least in small amounts.
Vitamin K1 | Vitamin K2 | Vitamin K3 |
---|---|---|
contained in green plants (e.g. broccoli) | formed by bacteria in the gut, or ingested through animal/fermented foods | synthetic vitamin |
responsible for blood clotting | responsible for blood clotting, calcium transport, and more | used only as a component of pet food |
Vitamin K2 is produced by bacteria and is therefore often found in animal foods such as eggs, meat and dairy products. It can also be ingested through fermented foods. A well-known example of this is Japanese natto. This is a traditional dish made from fermented soybeans that is particularly high in vitamin K2.

Vitamin K2 is mainly found in animal products such as dairy products or eggs. The good news for vegans: Vitamin K2 is also found in fermented foods (e.g. soy dishes or sauerkraut). (Image source: pixabay / silviarita)
In the human body, the vitamin is mainly found in the intestines(1). The special thing is that the intestine can also produce vitamin K2 itself with a healthy, balanced diet. From there, the vitamin K2 is distributed in the blood and can fulfill its tasks in the body.
How does vitamin K2 work in the body?
Vitamin K2 initiates many different processes in the body. In summary, for example, it has the following tasks:
- to clot the blood when injured
- Transport calcium from the blood to the bones
- to strengthen the bones
- to protect the bloodstream from deposits
- to prevent diabetes
- to support the metabolism
- to protect the cells.
The most well-known functions of vitamin K2 are strengthening bones and supporting blood clotting. In the following paragraphs we want to explain what exactly is behind it and which other functions vitamin K2 can have.
Vitamin K2 for blood clotting
When you injure yourself, in most cases you can see that the bleeding stops on its own after a few minutes. This is a vital mechanism, without which one could quickly bleed to death from even a small wound.
Coagulation factors are responsible for blood clotting. These are different proteins that ensure that wounds can close. However, in order for the proteins to work, they must first be activated. And this is where vitamin K2 comes into play: it triggers a chemical reaction that allows the clotting factors to become active.
Vitamin K2 for bone density
In our bones, building and breaking down processes are constantly at work. However, if the degradation processes become too severe, the bone can become brittle and unstable. This is the case, for example, with osteoporosis.
Vitamin K2 suppresses bone breakdown by activating the protein osteocalcin. It also moves calcium from the blood to the bones where it's needed for strength(2).
The process by which minerals such as calcium are stored in the bones is called mineralization. This is a basic requirement for bones to be able to form at all.
Vitamin K2 is not only involved in the mineralization of bones. It does the same job for the teeth as well.

Vitamin K2 brings calcium to the bones where it is needed to strengthen the structure. If this mineral is missing, the bones break more easily. (Image source: pixabay / lukaszdylka)
A combination of vitamin K2 and vitamin D(3) is particularly helpful for the bones. Because vitamin D supports both the build-up and breakdown processes in bones. If vitamin K2 is then added, it inhibits the degradation effect, so that mainly bone formation is active.
Vitamin K2 is therefore not directly responsible for strengthening the bones, but activates the responsible proteins.
Vitamin K2 against calcium deposits
The fact that vitamin K2 activates proteins is also important to prevent the arteries from calcifying(6). Vitamin K2 also triggers a chemical reaction here, through which the proteins - in this case so-called Gla proteins - can develop their effect. The blood vessels are cleaned and kept free.

So that the blood can flow unhindered, it is important that no deposits form in the bloodstream. Vitamin K2 helps to avoid such deposits. (Image source: pixabay / Vector8DIY)
Because when the arteries become clogged with deposited calcium, it can lead to strokes and heart disease. Various studies have already been able to show a connection between an adequate intake of vitamin K2 and a lower risk of cardiovascular diseases(7.8">.
Vitamin K2 against diabetes
The protein osteocalcin not only strengthens bones, but also increases the body's sensitivity to insulin(4).
Insulin is a hormone that regulates blood sugar. In diabetes, the body has too little of this hormone. Vitamin K2 can now ensure that the little insulin is used better and stimulate new insulin production, so that no blood sugar disease develops in the first place. This is how vitamin K2 prevents diabetes.
While vitamin K2 does not cure diabetes, it can help protect against diabetes in the first place.
The connection between a high vitamin K2 content in the body and a lower risk of developing diabetes has been proven in scientific studies(5).
Other functions of vitamin K2
Like all vitamins, vitamin K2 is said to have a positive effect on general well-being. A few effects of vitamin K2 on overall body and mind health have already been found:
Vitamin K2 protects against oxidative stress. This is a disruption in cell functions that can damage the entire cell. It is also said to support metabolism and strengthen brain functions along with other K vitamins(9).
Some research suggests that vitamin K2 plays an important role in protecting the body from cancer. There is evidence that the vitamin prevents cancer cells from growing. Vitamin K2 could prevent the onset of liver or prostate cancer, particularly in the case of risky pre-existing conditions(10,11">.
How strong this connection is, however, is still being researched. It is also important to note that vitamin K2 – just like with diabetes – can have a preventive effect, but cannot cure it.
General: In order to keep fit and protect your body, it is good to eat a diet rich in vitamin K2.
Side Effects and Interactions
Vitamin K2 has no known side effects, even in high doses. While other vitamins can lead to hypervitaminosis, i.e. vitamin overdose, vitamin K2 is harmless even in large quantities(13).
However, caution is advised if you are taking blood-thinning medication. Because of its influence on blood clotting, vitamin K2 can weaken the effect of such drugs. Foods containing vitamin K2 are therefore often not recommended during therapy with blood thinners or anticoagulants(12).
Additional intake of vitamin K2 preparations
Vitamin K2 is found in many foods: meat, eggs, dairy products and fermented foods such as certain soy dishes or sauerkraut. Therefore, a balanced diet is usually sufficient to supply the body with enough vitamin K2.
However, in the case of severe deficiency, vitamin K2 can also be taken as a dietary supplement.

If the body lacks vitamins, artificial vitamin supplements can be prescribed. You can buy vitamin K2 as drops, for example. (Image source: pixabay / Mareefe)
However, taking extra vitamins on your own is not always recommended. In the next paragraphs, we will explain when you should take additional vitamin K2 and when it is better not to.
When should I also take vitamin K2 supplements?
With a balanced diet, vitamin K2 deficiency is rare. However, people who take medication, are ill or eat an unhealthy diet may not have enough vitamin K2 in their bodies.
In most cases, the intake of vitamin K2 through food is sufficient. In the case of acute deficiency symptoms, however, an artificial preparation can also be recommended.
An acute lack of vitamin K2 usually manifests itself in frequent nose or gum bleeding and a strong reaction of the body to injuries: If bruises form quickly or even small wounds bleed for a long time, this can be due to insufficient vitamin K2. Bones and teeth are also weakened by a lack of vitamin K2. However, this is a point that is rarely noticed in everyday life.
In the case of such deficiency symptoms, artificial vitamin K2 preparations can be taken to replenish the vitamin balance. Which dose is necessary and whether a change in diet could be sufficient should be discussed with a doctor.
The MK7 all-trans is the most effective variant of vitamin K2 preparations. This is a form of vitamin K2 that works most effectively due to its chemical structure. The best way to find out where you can buy such a preparation and what you should pay attention to is to talk to your family doctor.
When should I not take vitamin K2 supplements?
As already described above, vitamin K2 can weaken the effect of blood-thinning medication. If you have to take such medication, you should definitely avoid artificial vitamin K2 intake.
In general, unless your doctor recommends it, you do not need to take vitamin K2 supplements yourself. If you suspect you are deficient in vitamin K2, you should first eat fermented or animal foods before resorting to artificial vitamins.
Conclusion
Vitamin K2 is an important part of our food and body. It activates various proteins and thus sets vital functions in motion. In the event of injuries, the wound can close thanks to vitamin K2, arteries are kept free of calcium deposits and the bone structure is strengthened. These three effects have been intensively scientifically studied and form the main functions of vitamin K2. In addition, vitamin K2 can prevent diabetes and the development of cancer.
In general, vitamin K2 is sufficiently well absorbed through food. An artificial vitamin K2 preparation can only be prescribed in the event of severe deficiency symptoms. The most effective form of such supplements is vitamin K2 MK7 all-trans.