Vitamin K2 Deficiency: Everything you need to know

Vitamin K2 Deficiency: Everything you need to know

We all know how important it is to eat a balanced diet filled with vitamins and minerals, but did you know that there’s one vitamin in particular that you’re probably missing out on?

We’re here to tell you everything you need to know about vitamin K2, an essential nutrient that way too many of us are deficient in. By the end of this article, you’ll understand exactly why vitamin K2 deficiency is so common as well as what you can do to avoid it.

Vitamin K2 deficiency occurs when the body is not consuming enough of this nutrient via diet or supplementation. Vitamin K2 deficiency is particularly common among those living in the western hemisphere.

But don’t worry - if you want to support your heart and bone health, we have all the answers on how vitamin K2 supplements can work to prevent or fix a deficiency in this nutrient.

What is vitamin K2?

Vitamin K is a fat soluble vitamin that offers many important health benefits, as it assists in the following functions:

  • Blood coagulation
  • Supporting bone health
  • Supporting healthy blood vessels
  • Reducing risk of heart disease

However, it’s important for us to realize that there are two forms of this essential vitamin: vitamin K1 and K2.

Vitamin K1 vs vitamin K2

When people talk about vitamin K, they are generally referring to vitamin K1. 

This is because when vitamin K was initially being studied, researchers believed that the structures of K1 and K2 were too similar to have any significant differences in function. 

But this is untrue, as vitamin K2 actually offers unique benefits that are separate from the blood coagulating effects of vitamin K1.

Not only does K2 play an important role in blood coagulation, but this specific nutrient is also responsible for improving bone and heart health by removing the build-up of calcium from blood vessels and transporting it to our bones and teeth.

That’s why we need to make sure we’re not only maintaining adequate vitamin K levels, but that we’re intaking enough vitamin K2 specifically to avoid a deficiency in this niche nutrient.

What is vitamin K2 deficiency?

A vitamin K2 deficiency occurs when we aren’t consuming enough of this nutrient to maintain proper levels and support our health.

Side effects of vitamin K2 deficiency

A vitamin K deficiency may increase our risk of developing the following side effects:

  • Excessive bruising
  • Excessive bleeding
  • Blood clotting
  • Heart disease
  • Osteoporosis

That’s why we should all be making an effort to consume enough vitamin K2 to avoid a deficiency - but there are some groups who need to make even more of an effort than others.

Who’s at risk for vitamin K2 deficiency?

Anyone in the western hemisphere

Studies explain that adequate consumption of vitamin K2 is rare even in a healthy Western diet. 

This is because foods that are rich sources of vitamin K2 are not traditionally eaten in this area of the world, as they include:

  • Natto
  • Eel 
  • Beef liver
  • Egg yolk

Very few of us are eating enough of these foods to derive the recommended amount of vitamin K2, which is why supplementation of this nutrient is typically necessary.

Vegans and vegetarians

Considering that vitamin K2 is already rare in the average western diet, it is even more difficult to obtain for anyone with diet restrictions.

That’s why vegans and vegetarians are one of the most likely demographics to develop a deficiency in vitamin K2. The richest sources of K2 consist of animal and dairy products, which is why plant-based eaters need to seek out alternative sources.

Vegan Sources of vitamin K2

While there are limited vegan sources rich in this essential nutrient, vegans can add these foods to their diet to increase their intake.

  • Natto (fermented soybeans)
  • Sauerkraut
  • Tempeh
  • Pickles
  • Kimchi
  • Miso
  • Kombucha

For a complete list with more information, check out our article: 9 Best Vegan Sources of Vitamin K2

Pregnant women

Many pregnant women take vitamin K prenatal supplements to avoid developing a deficiency in vitamin K1.

But considering that vitamin K2 deficiencies are even more common than K1, expectant mothers must make an extra effort to obtain this nutrient to support a healthy pregnancy.

In fact, vitamin K2 has been studied for its use as a safe treatment option in cases of pregnancy-associated osteoporosis. That’s why this demographic in particular should consider adding a daily vitamin K2 supplement to their diet.

How much vitamin K2 do I need?

It’s important for us to understand exactly how much vitamin K2 we need in our diet to avoid a deficiency. 

However, there is no specific recommended dietary intake (RDI) for this form of vitamin K, despite the studies that argue it should have one, as it meets all the criteria. 

That’s why we have to use the recommendations that health professionals have provided to ensure adequate intake of vitamin K in general.

See the table below to determine how much vitamin K2 your demographic should be consuming to ensure optimal health.


Life Stage

Recommended amount of vitamin K2 per day

Birth to 6 months

2 mcg

7-12 months

2.5 mcg

1-3 years

30 mcg

4-8 years

55 mcg

9-13 years

60 mcg

14-18 years

75 mcg

Adult men 19 years and older

120 mcg

Adult women 19 years and older

90 mcg

Pregnant or breastfeeding teens

75 mcg

Pregnant or breastfeeding women

90 mcg


For anyone not getting enough vitamin K in their diet, supplements can be a great tool. However, vitamin K supplements generally contain K1, and not K2


That’s why FuelOrganics offers a high-quality vegan vitamin K2 supplement perfect for vegans (and anyone) looking to experience the benefits of this essential nutrient and support a healthy heart and bones.


Final thoughts

Vitamin K2 may be rare in the average western diet, but that doesn’t mean we have to be deficient in this vital nutrient.


By staying knowledgeable about vitamin K2 sources and the dietary supplements that can support our intake, we can consume enough vitamin K2 to avoid a deficiency and experience optimal heart and bone health.

Trusted sources

  1. Maresz K. (2015). Proper Calcium Use: Vitamin K2 as a Promoter of Bone and Cardiovascular Health. Integrative medicine (Encinitas, Calif.), 14(1), 34–39.
  2. Brown, B., & Wright, C. (2020). Safety and efficacy of supplements in pregnancy. Nutrition reviews, 78(10), 813–826.
  3. Akbulut, A. C., Pavlic, A., Petsophonsakul, P., Halder, M., Maresz, K., Kramann, R., & Schurgers, L. (2020). Vitamin K2 Needs an RDI Separate from Vitamin K1. Nutrients, 12(6), 1852.
  4. Vitamin K. Fact sheets for consumers. National Institutes of Health. Office of Dietary Supplements. Retrieved from


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