nutrition

Medically Reviewed

Vitamin K2: Are You Getting Enough? The Benefits Explained

jars of fermented foods

Vitamin K2 is a main form of vitamin K and it boasts particular health benefits. Read on to learn more.

What is vitamin K?

Vitamin K is a fat-soluble vitamin that’s essential for blood clotting.

What you may not know is that the term “vitamin K” actually refers to a family of compounds. These compounds can be divided into two general camps: vitamin K1 (phylloquinone) and vitamin K2 (menaquinones). You can find both of these forms of vitamin K in a variety of food sources. Both forms are essential for blood, heart, and bone health.

The adequate intake (AI) of vitamin K is considered to be 90-120 mcg per day.

Types of vitamin K

Both main forms of vitamin K – K1 and K2 – are essential for the health of your body. Vitamin K is especially important for helping your body with healthy blood clotting. Moreover, vitamin K helps promote the calcification of your bones through a hormone called osteocalcin.

Vitamin K1 is found naturally in plant foods, while vitamin K2 is found in animal foods and fermented foods.

Some researchers attest that K1 and K2 have different effects and benefits, but more studies are needed to fully demonstrate this. Some studies have found, though, that vitamin K2 supplements were more effective than vitamin K1 supplements at supporting bone and heart health. Indeed, the K1 group saw no significant benefits.

Your body can convert some K1 into K2.

Vitamin K2 benefits

Vitamin K2 and bone health

Vitamin K2 plays an important role in your body’s metabolism of calcium, which is the main mineral in your bones and teeth. It activates calcium-binding activity in two proteins, osteocalcin and matrix GLA protein, which in turn helps your body maintain healthy bones.

Findings from some studies strongly suggest that K2 can benefit bone health in big ways. A three-year study of postmenopausal women, for example, found that vitamin K2 supplements helped shore up bone mineral density. Another study found that higher levels of vitamin K2 intake were linked to more bone matrix formation.

Vitamin K2 and skin health

While there haven’t been any studies specifically observing the effects of vitamin K2 on skin health, research has definitively shown that vitamin K2 supports healthy blood flow. Healthy blood flow is very important for skin health.

Another study suggested vitamin K2’s potential benefits for skin health, finding that elastin, an abundant protein in the skin, gets calcified through the natural aging process. One hypothesis posits that vitamin K2’s role in managing the body’s calcium levels may impact the skin’s storage of elastin and thereby support skin health overall.

Vitamin K2 and brain health

This study looked at some of the potential benefits of vitamin K2 beyond bone health and cardiovascular health. One area that’s gotten recent attention is vitamin K2’s involvement in the development and survival of brain cells. Furthermore, vitamin K2 has been shown to be involved in the synthesis of sphingolipids, which are an important class of lipids found in brain cell membranes. Sphingolipids participate in the signaling, proliferation, differentiation, transformation, and survival of brain cells.

Vitamin K2 and cardiovascular health

Vitamin K2 is well known for its support of cardiovascular health. It activates the matrix GLA protein, which prevents excess deposits of calcium on the wall of your blood vessels; this, in turn, supports healthy blood flow and circulation. Anything that prevents calcium buildup in your arteries is ultimately good for the health of your heart and blood vessels. One 7-10 year study found that people with higher intakes of vitamin K2 experienced better overall heart health. It should be noted that, in the same study, vitamin K1 intake didn’t produce comparable results.

Vitamin K2 and dental health

Recent research points to the likelihood that vitamin K2 can boost dental health. This study, for example, looked at the relationship between vitamin K2 and reactive oxygen species (ROS) in the mouth. In the study, sugar was found to increase ROS and reduce dentinal fluid flow, which in turn makes teeth more sensitive to bacteria in the mouth. Vitamin K2 has antioxidant-like properties that can restore dentinal flow.

Vitamin K2 also activates osteocalcin, which is one of the main regulating proteins in dental health. Osteocalcin helps grow new bone and new dentin, which is the vitally important calcified tissue just beneath your teeth’s enamel.

Other health benefits

While additional research is needed, some preliminary animal studies suggest that use of MK-4 (a type of vitamin K2) can promote testosterone production. Another study found that vitamin K2 has the potential to support insulin levels in healthy individuals.

Foods high in vitamin K2

Some foods rich in vitamin K2 include:

  • Natto (fermented soy)
  • Hard cheese (gouda)
  • Soft cheese (blue cheese)
  • Miso
  • Egg yolk
  • Butter
  • Sauerkraut
  • Salami
  • Chicken breast

Vitamin K2 supplementation

Potential side effects and adverse reactions

According to this study, there haven’t been any cases reported of vitamin K toxicity. Before taking a vitamin K supplement, though, it’s still important to talk to your doctor about whether this is right for you. You should also talk about any other medications you are taking, since these may interact with a new supplement.

Final Takeaways

Vitamin K is a fat-soluble vitamin that comes in two main forms: vitamin K1 and vitamin K2.

Both are important for blood coagulation, as well as bone and heart health. Studies have shown that vitamin K2 supplementation is better than K1 supplementation at supporting bone and heart health, however. More studies of the roles of different vitamin K forms are necessary.

Furthermore, vitamin K2 may be beneficial for dental health, skin health, and brain health. Some researchers think that certain subpopulations should regularly make use of vitamin K2. It’s clear that vitamin K2 boasts a range of benefits.

In addition to supplementation, you can boost your vitamin K intake through adjustments to your diet. Vitamin K1 and vitamin K2 are available in a number of tasty food sources. (You can get vitamin K1 from boiled spinach, cooked broccoli, kidney beans, yogurt, and more.)

Talk to a medical professional about your vitamin K needs and see if a vitamin K2 supplement is right for you.

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