How do you get vitamin K2 in your system?

January 13, 2026 •

4 min read

While many are familiar with Vitamin K1 found in leafy greens, Vitamin K2 is less known but equally vital for health. A 2022 meta-analysis of 16 studies involving postmenopausal women found that vitamin K2 supplementation positively affected bone mineralization and strength. Learning how to get vitamin K2 in your system is crucial for directing calcium to the right places, such as bones, and away from arteries.

Quick Summary

Obtain vitamin K2 from specific food sources like fermented foods, organ meats, and grass-fed dairy, or through supplements, to promote better bone and cardiovascular health.

Key Points

Rich Food Sources: To get vitamin K2, consume fermented foods like natto, hard cheeses, and sauerkraut, as well as animal products like organ meats, grass-fed dairy, and egg yolks.
K2 Subtypes: MK-7 is found in fermented foods and is longer-lasting in the body, while MK-4 is found in animal products and is quickly metabolized.
Enhance Absorption: Since vitamin K2 is fat-soluble, consume it with a healthy fat source like olive oil, avocado, or nuts to improve absorption.
Pair with Vitamin D: K2 and Vitamin D work synergistically, so a combined supplement or dietary approach can maximize benefits for bone and cardiovascular health.
Consider Supplements: For those with dietary restrictions or low intake, high-quality MK-7 supplements are an effective way to ensure adequate vitamin K2 levels.
Important Consultation: If you take blood-thinning medication (e.g., warfarin), consult a doctor before increasing K2 intake, as it can affect blood clotting.

What is Vitamin K2 and Why is it Important?

Vitamin K is a family of fat-soluble vitamins, primarily divided into two forms: Vitamin K1 (phylloquinone) and Vitamin K2 (menaquinone). While K1 is primarily involved in blood clotting and found abundantly in leafy green vegetables, K2 has distinct and critical functions related to calcium regulation. It is responsible for activating proteins, such as osteocalcin and matrix Gla-protein (MGP), that help direct calcium to your bones and teeth, and prevent its buildup in soft tissues like arteries. This dual action is essential for maintaining strong bones and promoting cardiovascular health. A deficiency in Vitamin K2 is not uncommon in Western diets, which are often low in K2-rich foods.

Dietary Sources of Vitamin K2

There are two main subtypes of Vitamin K2: MK-4 and MK-7, each found in different foods. The MK-4 form is primarily found in animal products, while the longer-lasting MK-7 is produced during bacterial fermentation.

MK-7 Rich Fermented Foods

Natto: This traditional Japanese dish of fermented soybeans is the most concentrated food source of MK-7 by far. Though it has a strong, pungent flavor and sticky texture, even small amounts can provide a significant dose of K2.
Hard and Soft Cheeses: Cheeses like Gouda, Brie, and some cheddars contain varying but notable amounts of Vitamin K2, produced by the fermenting bacteria.
Sauerkraut: Made from fermented cabbage, sauerkraut is another fermented food containing Vitamin K2.
Kefir: This fermented milk drink contains probiotics that can produce Vitamin K2.

MK-4 Rich Animal Products

Organ Meats: Liver from goose, chicken, and beef is a potent source of MK-4.
Egg Yolks: Pasture-raised egg yolks are a good source of MK-4.
Grass-Fed Butter and Dairy: Dairy products from grass-fed animals contain more MK-4 than those from grain-fed animals.
Fatty Meats: Chicken thighs and other fatty cuts of meat contain moderate levels of MK-4.

Comparison of K2 Subtypes: MK-4 vs. MK-7


Feature	MK-4 (Menaquinone-4)	MK-7 (Menaquinone-7)
Primary Source	Animal products (organ meats, egg yolks, grass-fed dairy)	Fermented foods (natto, some cheeses)
Bioavailability	Quickly disappears from circulation; low bioavailability	Stays in the bloodstream for a longer period (longer half-life)
Efficacy	Effective at higher, more frequent doses	Effective at smaller doses due to better accumulation
Commonality in Diet	Present in fewer, less-consumed foods for many	Easily accessible in natto, though flavor is often an acquired taste
Health Focus	Supports general K2 functions; abundant in brain and testes	Excellent for bone and cardiovascular health due to systemic presence

How to Enhance Absorption and Utilize Supplements

For optimal absorption, Vitamin K2, being fat-soluble, should always be consumed with a source of fat. For example, adding some olive oil to a salad with cheese or eating eggs alongside avocado can increase absorption. Pairing Vitamin K2 with Vitamin D is also beneficial, as they work synergistically to regulate calcium.

Many individuals, particularly those following a vegetarian or vegan diet, may find it challenging to obtain sufficient K2 from food alone. In such cases, supplementation can be a practical option. Supplements often contain the more bioavailable and longer-lasting MK-7 form, which is derived from natto.

Before starting any supplement regimen, especially if you take blood thinners like warfarin, it is critical to consult a healthcare provider. Vitamin K can interact with blood-clotting medications and disrupt their effects.

The Overlooked Benefits of Vitamin K2

Historically recognized for its role in blood clotting, Vitamin K2's broader benefits for bone and heart health are now widely recognized. It has been shown to reduce the risk of arterial calcification and heart disease. A high dietary intake of K2 is linked with a lower risk of coronary heart disease. Furthermore, it activates osteocalcin, a protein that binds calcium to the bone matrix, improving bone density and reducing fracture risk, especially in postmenopausal women. Emerging research is also exploring K2's potential benefits for brain health, insulin sensitivity, and cancer prevention. For example, low serum vitamin K2 levels have been observed in individuals with multiple sclerosis. Consistent consumption of Vitamin K2, whether through diet or supplementation, is a cost-effective way to improve long-term health.

Conclusion

To get vitamin K2 in your system effectively, focus on incorporating a combination of fermented foods and animal products into your diet. For the potent MK-7 form, consider adding natto or aged cheeses. For MK-4, opt for organ meats, grass-fed butter, and pasture-raised eggs. As a fat-soluble vitamin, consuming K2 alongside healthy fats will maximize absorption. For those who cannot get enough from diet alone, high-quality supplements containing MK-7 are a viable alternative. Always consult a healthcare professional before starting supplements, particularly if you are on anticoagulant medication.

Visit this page for additional information on Vitamin K's diverse roles in health

Frequently Asked Questions

Vitamin K1 (phylloquinone) is primarily found in leafy green vegetables and is essential for blood clotting. Vitamin K2 (menaquinone) is found in fermented foods and animal products and is crucial for regulating calcium, supporting bone and heart health.

Natto, a traditional Japanese dish of fermented soybeans, is the richest food source of Vitamin K2 (specifically MK-7). One tablespoon can provide a very high concentration of this nutrient.

It can be more challenging for vegetarians and vegans to get sufficient Vitamin K2, as many rich sources are animal-based. Fermented foods like natto and sauerkraut are options, but supplementation may be necessary to ensure adequate intake, especially of the MK-4 subtype.

Since Vitamin K2 is fat-soluble, consuming it with a source of dietary fat will significantly improve its absorption. Examples include having eggs with avocado or a cheese dish with olive oil.

Vitamin K2 is vital for directing calcium to the bones and teeth, thereby improving bone density and potentially reducing the risk of osteoporosis. It also helps prevent calcium buildup in arteries, supporting cardiovascular health.

Getting nutrients from whole foods is often preferred, but many K2-rich foods are not staples in Western diets. High-quality supplements, particularly those containing the MK-7 form, can be a reliable way to ensure adequate intake, especially if dietary sources are limited.

Individuals taking anticoagulant (blood-thinning) medications like warfarin should consult their doctor before increasing their Vitamin K2 intake, as it can affect the drug's effectiveness.