What is Vitamin K2 Good For?

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When it comes to all of the essential nutrients that your body needs in order to stay healthy and strong, you are likely familiar with vitamin K. However, vitamin K2 specifically may not sound as familiar.

While the two K vitamins are often referred to as one and the same, vitamin K is actually made up of two different forms, K1 and K2, and building a better understanding of how these vitamins differ, what they do for your body, and how they may help you identify gaps in your diet.

That being said, this is your complete guide to vitamin K, specifically vitamin K2, and how it works to support your overall health and well-being.

Vitamin K: Why Is It Important?

Vitamin K is one of several fat soluble vitamins, and it comes in two main forms called vitamin K1 and vitamin K2.

Vitamin K1 is known as phylloquinone, and this vitamin is found in dark, leafy greens such as kale, spinach, and collard greens, and vitamin K2 is known as menaquinone and can be found in fermented foods and some animal foods.

Vitamin K is an important part of a healthy diet because it works to help make various proteins that are needed for your body to form blood clots as well as build and maintain strong and healthy bones.

More specifically, vitamin K helps make the proteins prothrombin and osteocalcin, which work to form blood clots and produce healthy bone tissue.

Vitamin K is broken down by theory and is then excreted through your urine or stool. This makes it very difficult to reach toxic levels of this vitamin, and may also make it very easy to end up with insufficient vitamin K levels if you do not eat a variety of food sources for this vitamin.

Vitamin K1 vs. K2: What’s the Difference?

Vitamin K comes in two main forms, which are vitamin K1 and vitamin K2.

Because both of these forms are still vitamin K, it may be easy to think that they work in similar ways in your body, but these two types of vitamin K are not one and the same.

While vitamin K1 is primarily found in leafy greens, vitamin K2 is made by bacteria, which is why it is mostly found in dairy products or fermented foods. Even more, vitamin K2 is actually split into two further subgroups, which are MK4 and MK13, and K2 is thought to have more of a protective benefit for your bones than K1.

Having a deficiency in either vitamin K1 or vitamin K2 can lead to negative effects on your health. So, even if vitamin K2 is more protective as compared to K1, it is still important that you are getting enough of both types of vitamin K.

Inadequate levels of vitamin K in your body can lead to an increased risk of bone fractures due to low bone density. One study even found that women who consume less than 109mcg of vitamin K each day are more likely to end up breaking a hip.

Generally, the recommended daily intake of vitamin K is about 120mcg for men and 90mcg for women, but these levels may vary depending on each individual’s needs.

Vitamin K deficiencies can cause symptoms like easy bruising and an inability of your blood to clot the way that it should, and vitamin K deficiency can generally be avoided by making sure to get enough of this nutrient from your food or from supplements.

How Vitamins K2 and D3 Work Together

While vitamin K2 has plenty of benefits in its own right, it also becomes extremely beneficial when ingested alongside adequate amounts of vitamin D3.

Most often, calcium is cited as the nutrient with the most benefits when it comes to bone health, but vitamins K2 and D3 may be just as important.

An inadequate intake of calcium can, of course, lead to decreased bone density, but vitamin K2 and vitamin D3 are equally as critical because they impact the way that your body absorbs and uses calcium. Not to mention, they also have an effect on whether or not your body ends up using the calcium you ingest to help support and maintain healthy bones.

Some scientific evidence suggests that consuming unnecessary or excessive calcium supplements may increase the risk of developing heart disease because the excess calcium leads to calcium deposits in blood vessel walls.

In other words, extra calcium that you consume may end up being misused by your body and can then build up in places where you do not want it to, and this is part of the reason why vitamins K2 and D3 are so essential.

Vitamin K2 may even help improve arterial elasticity, and may work to help ward off age-related arterial stiffening. Essentially, vitamin K2 can help your body optimize the way it uses the calcium you ingest in order to prevent negative health effects and promote strong and healthy bones.

Vitamin D3 also plays a key role when it comes to the calcium in your body, specifically in regards to calcium absorption and bone mineralization.

These two processes ultimately contribute to your body’s overall ability to maintain a healthy bone mineral density as well as prevent certain health conditions. Insufficient amounts of vitamin D3 in the body have been linked to increased bone metabolism and an increased risk of bone fractures.

That said, vitamin K2 and vitamin D3 work together to ensure your absorption and utilization of calcium are regulated and maintained. Vitamin D3 works to help make sure you have enough calcium in your body, and vitamin K2 helps ensure that the calcium in your body is being distributed appropriately by directing it towards your bones and teeth and helping to prevent an accumulation of calcium in your soft tissues.

Even more, vitamins K2 and D3 also go hand in hand with magnesium, not just calcium. Magnesium, calcium, vitamin K2, and vitamin D3 all work together as a team, and magnesium, too, can help counterbalance any excessive calcium in your body.

These four nutrients are all intertwined when it comes to the way that they work in your body, and one cannot perform optimally without the others.

Additionally, if you choose to start taking supplements of one of these nutrients, it may be a good idea to begin supplementing the remaining three nutrients as well in order to make sure that you are meeting the recommended ratio of these vitamins and minerals.

For example, taking megadoses of vitamin D3, like those found in a supplement, without also taking supplemental doses of vitamin K2 and magnesium, could lead to a vitamin D3 toxicity or magnesium deficiency.

A good rule of thumb is to consult your doctor before you begin taking a new supplement, or to consult them once you have already started taking a new supplement so that they can offer proper guidance in terms of these kinds of health concerns.

Impact of Vitamin K on Health Conditions and Prevention

Vitamin K, and specifically vitamin K2, can have a variety of benefits when it comes to supporting different parts of your health.

Vitamin K2 and Bone Health

Research shows that vitamin K2 may help support bone health.

Your risk of having at least one bone fracture in your lifetime decreases by 25% with the daily use of supplements for vitamin D, vitamin K2, and calcium, but the exact percentage decrease of this risk does depend on how much of each vitamin is contained in the specific supplements you are using.

Vitamin K2 can help prevent fractures in your vertebrae by 60%, hip fractures by 77%, and nonvertebral fractures by 81% according to some studies, and vitamin K2 taken at 45 μgm per day may help maintain bone density.

Vitamin K2 supplementation may also work to soothe irritation and can help support joint health. Insufficient intake of vitamin K2 can lead to abnormal mineralization of your bones and cartilage, so making sure to get enough of this vitamin may work wonders for your health.

Vitamin K is such a key component of strong and healthy bones because of its ability to synthesize the protein called osteocalcin, and this protein helps maintain your bone strength. People living in the West particularly do not eat as much vitamin K as they used to, and thus may be at a higher risk of having a deficiency.

Taking 180mcg of vitamin K each day may help support healthy bone density even through old age, which may be especially important for women who are going through, or who have already gone through menopause. Taking certain forms of vitamin K2 can certainly help support bone strength as well as reduce the risk of bone fractures for older women who have weak bones, but the benefits may be lessened for older women whose bones are still strong.

Vitamin K2 and Heart Health

When it comes to the health of your heart, vitamin K2 factors in because of the way it activates certain proteins in your body.

When activated, some of these proteins can help prevent calcium from accumulating in your soft tissues, and one study showed that increasing vitamin K2 intake in women by 10 μgm could support heart health.

These same benefits were not found in studies of vitamin K1.

Vitamin K2 and Blood Sugar

Being deficient in vitamin K2 can lead to an increase in insulin resistance and may even reduce your body’s ability to clear out glucose from your bloodstream.

Vitamin K2 and Brain Function

One of the most important roles that vitamin K fulfills has to do with the synthesis of portions of your brain, and certain proteins that are, depending on sufficient amounts of vitamin K work to keep your peripheral and central nervous system strong and healthy.

Making sure you are getting adequate amounts of vitamin K may help support your cognitive function, and may even help support episodic memory.

How To Know if You Should Supplement Vitamin K: Signs of Deficiency

While a vitamin K deficiency is considered somewhat rare, it is still possible. There are certain risk factors that may increase a person’s likelihood of developing a vitamin K deficiency.

This includes:

  • Severe illness
  • Certain chronic conditions
  • Alcohol or drug abuse
  • Malabsorption, especially when malabsorption impacts absorption of fats due to
  • Certain health conditions
  • Certain medications, including antibiotics, antacids, and anti-seizure medications may interfere with vitamin K
  • High doses of aspirin, as this may make your recommended daily intake of vitamin K higher
  • Decreased storage of vitamin K in the liver due to certain health conditions
  • Dietary restrictions

There are certain signs and symptoms that can act as indications that you are dealing with a vitamin K deficiency, and in this case it may be important to start taking vitamin K supplements or changing your diet in order to get more vitamin K from your food.

Signs and symptoms of a vitamin K deficiency include:

  • Bruising very easily
  • Oozing from the nose or gums
  • Excessive bleeding from any wounds, punctures, injection sites, or surgical sites
  • Very heavy menstrual periods
  • Bleeding from the gastrointestinal tract
  • Blood in the urine and/or stool

Additionally, even infants can end up with a vitamin K deficiency, and their signs and symptoms may differ slightly from those of a vitamin K deficiency in an adult, but will be very similar.

A deficiency in vitamin K is discovered and diagnosed when excessive or unexpected bleeding occurs. If this is the case, a prothrombin time test may be performed in order to confirm the deficiency and investigate the cause of the bleeding.

If the result of this test is prolonged and is expected to be caused by levels of vitamin K that are too low, vitamin K is often given to the patient through an injection.

Once this leads to the bleeding stopping, a vitamin K deficiency may be the cause. Aside from a prothrombin time test, there are also other coagulation tests that may be performed in order to determine the cause of excessive bleeding or bruising.

In order to treat a vitamin K deficiency, oral supplements or injections may be recommended for short-term use. Lifetime or long-term usage of supplements may also be necessary for those with vitamin K deficiencies who are also dealing with underlying health conditions, and vitamin K supplements may take 2 to 5 days to start working after you begin to take them.

Consulting with a Doctor

You should always consult with your doctor before taking any new supplements, because your doctor can advise you in terms of dosage and proper usage, and they will also be able to give you any important information that you might need to know.

Because your doctor is already familiar with your medical history, they will be the best resource for you when it comes to the safety of certain products for your individual needs and situation.

Taking Supplements to Correct a Deficiency

It is also important to carefully follow the proper usage instructions on the label of the specific supplements you start to use so that you do not accidentally take too much, or too little, at a time. Some supplements should be taken with food while others are best taken on an empty stomach, and the usage instructions will offer guidance regarding this as well.

Additionally, vitamin K supplements, and all supplements in general, do have a risk to potentially interact with certain drugs, and this is another reason why it is so important to consult your doctor.

Vitamin K2 specifically may interact with Warfarin or other drugs that impact your body’s ability to form blood clots, so you should talk to your doctor if you are taking this medication or any other medications at all.

The Bottom Line

Vitamin K is just one of many essential nutrients that your body needs in order for you to stay strong and healthy, and it comes in two main forms: vitamin K1 and vitamin K2.

Vitamin K1 can be found in many forms of leafy greens, while vitamin K2 is mostly found in animal products, such as dairy products, as well as fermented foods.

Vitamin K2 is specifically very important because it is recognized as being more protective of your bones than vitamin K1, and thus may provide more benefits. That said, not getting sufficient amounts of either form of vitamin K can have negative effects, so it is important to make sure you are getting enough of both.

Aside from keeping your bones healthy, vitamin K2 can also have benefits when it comes to a healthy heart, healthy blood sugar and insulin levels, and even cognitive function.

Vitamin K2 helps regulate the way your body absorbs and uses the calcium that you ingest, meaning that vitamin K and calcium go hand in hand to keep you healthy.

While a vitamin K deficiency is rare in generally healthy people, this deficiency is still possible and may be recognized by easy bruising, excessive bleeding, heavy menstrual periods, or blood in the urine or stool. If you recognize these symptoms, you should pay your doctor a visit in order to find the cause.

Healthy Directions Staff Editor