MK-7 is one member of the K2 group
Vitamin K2 describes a family of menaquinones, not just one substance. MK-7 is menaquinone-7; the number refers to its side-chain structure, not a sevenfold potency rating. Natto is a food source of MK-7. K1 and other menaquinones remain distinct forms, even though they share vitamin K-related biological functions. [1]
Separate the mechanism from the outcome
Vitamin K-dependent proteins are involved in clotting, bone metabolism and vascular biology. These mechanisms motivate research; they do not by themselves prove that an MK-7 supplement prevents heart attacks, reverses arterial calcification or prevents fractures. The NIH ODS summary describes uncertainty about vitamin K forms and coronary disease. There is no separate U.S. intake recommendation specifically for MK-7. [1]
An example of reading a claim
Imagine a label names MK-7 and a promotion says it sends calcium to bones rather than arteries. The ingredient identity can be checked on the label, but the clinical claim needs outcome evidence for the relevant population and dose. Someone taking warfarin should discuss any vitamin K supplement with their treating team rather than assuming K2 escapes the interaction. [1]
| Hypothetical label or claim | Interpretation |
|---|---|
| Vitamin K2 as MK-7 | Identifies a particular menaquinone |
| Supports bone biology | Not the same as proven fracture reduction |
| Safe with every blood thinner | Requires medication-specific assessment |
Sources for this article
- Vitamin K - Health Professional Fact Sheet
Source consulted: 2026-09-20. This is a reference resource, not a claim that we conducted the studies or tested a product.
Considering a supplement?
Ingredient evidence alone does not establish which retail product is suitable. No single featured product is recommended for this article.
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