Quick summary

Vitamin K2 MK-4 is a fat-soluble form of Vitamin K belonging to the menaquinone family, specifically menaquinone-4. It is one of the biologically active forms of Vitamin K2, involved in processes such as calcium metabolism and blood clotting.

What is it?

Vitamin K2 MK-4, also known as menaquinone-4 (MK-4), is a subtype of the vitamin K2 group within the broader vitamin K family. Vitamin K vitamins are fat-soluble compounds important in various physiological functions. MK-4 differs chemically from the phylloquinone (Vitamin K1) found mainly in plants, as MK-4 contains a shorter side chain and is typically found in animal-derived foods as well as some fermented products, although specific food sources for MK-4 are not detailed in the available data.

Main functions in the body

  • Supports blood clotting by activating several clotting factors.
  • Contributes to calcium metabolism, potentially influencing bone health.

Recommended intake and upper limit

There are no separate Recommended Dietary Allowance (RDA) or Adequate Intake (AI) values established specifically for Vitamin K2 MK-4. Current intake recommendations generally apply to total Vitamin K intake, encompassing both K1 and K2 forms.

No established upper intake level (UL) exists specifically for Vitamin K2 MK-4.

Official bodies like the U.S. National Institutes of Health Office of Dietary Supplements (NIH ODS) do not differentiate distinct intake levels for MK-4 from other forms of Vitamin K.

Best food sources

Detailed food sources specifically for Vitamin K2 MK-4 are not provided in the available information. Generally, Vitamin K2 forms are found in some animal products and fermented foods; however, no specific guidance about MK-4-rich foods is available here.

Deficiency: causes, symptoms and risk groups

No deficiency data specific to Vitamin K2 MK-4 is provided separately. In general, vitamin K deficiency relates primarily to bleeding disorders due to insufficient activation of clotting factors. Risk groups and symptoms specific to MK-4 deficiency are not described.

Supplement forms

  • Vitamin K2 MK-4 supplements are available, often labeled as menaquinone-4 (MK-4).

Potential benefits: what does the evidence say?

Bone health and calcium metabolism

Current evidence is insufficient to draw conclusions about the specific benefits of Vitamin K2 MK-4 supplementation on bone health or calcium metabolism. No distinct clinical studies or supplementation trials focused on MK-4 were provided in the data.

Blood clotting

Vitamin K, as a nutrient group including various forms such as K1 and K2, is well-established as essential for normal blood clotting through activation of clotting factors. Although this role is broadly accepted for Vitamin K, no MK-4 specific clinical evidence was supplied.

Side effects and toxicity

No common side effects or toxicity data specific to Vitamin K2 MK-4 were provided. There are no known upper intake warnings directly associated with MK-4.

Drug and nutrient interactions

No information on drug or nutrient interactions specific to Vitamin K2 MK-4 was supplied.

Who should be careful?

As with all forms of Vitamin K, individuals who are pregnant, breastfeeding, have medical conditions, or are using medications (particularly blood thinners like warfarin) should consult a qualified healthcare professional before starting supplementation.

Frequently asked questions

  • Is Vitamin K2 MK-4 different from Vitamin K1? Yes, Vitamin K2 MK-4 is a different chemical form of Vitamin K from Vitamin K1, with specific structural differences and possibly different roles in the body.
  • Should I take MK-4 supplements for bone health? Currently, there is insufficient evidence to support MK-4 supplementation specifically for bone health benefits.
  • Are there any risks in taking MK-4 supplements? No specific side effects or toxicity have been reported for MK-4, but consultation with a healthcare professional is recommended, especially if you take medications or have health issues.
  • Is there an official recommended daily dose for MK-4? No separate official intake recommendations exist for MK-4 distinct from total Vitamin K intake guidelines.

Evidence limitations

  • No clinical trials or supplementation studies specific to Vitamin K2 MK-4 were provided.
  • No separate intake recommendations or deficiency data specific to MK-4 are available.
  • No detailed toxicity or interaction information specific to MK-4 was found.
  • Overall evidence for MK-4’s distinct effects remains insufficient based on the current data.

References

  • PubMed IDs were provided without supporting abstracts or study details; therefore, no direct study links or references are included here.

Disclaimer: This page provides information based on currently available evidence. It is not intended to provide medical advice, and no health claims are authorized specifically for Vitamin K2 MK-4. Individuals considering supplements, especially those who are pregnant, breastfeeding, have existing medical conditions, or are taking medications, should seek guidance from a healthcare professional.

Last reviewed: June 2024