Natto vs Nattokinase vs Vitamin K2: What’s the Difference?
Natto, nattokinase, and vitamin K2 (MK-7) are related but they’re not interchangeable. This article breaks down the simplest way to understand each: natto is the whole fermented food, nattokinase is one enzyme made during fermentation, and MK-7 is a vitamin found in natto linked to bone-related pathways. You’ll also learn why these terms get blurred online, when each one makes sense, and the key cautions for anyone on blood thinners like warfarin.
These three terms are often confused because they’re related, but they are not the same thing. The simplest way to understand it is:
- Natto = the fermented food (the whole “package”)
- Nattokinase = one enzyme made during natto fermentation
- Vitamin K2 (MK-7) = a vitamin found in natto that supports bone-related pathways.
Once you separate them, the topic becomes much clearer.
Natto is a traditional Japanese food made by fermenting soybeans with a specific bacterium. Because it’s a whole fermented food, natto naturally contains a combination of nutrients and fermentation by-products rather than one isolated compound.
Natto may contain:
- Fermented soy proteins and peptides
- Naturally occurring vitamin K2, including MK-7
- Enzymes produced during fermentation, including nattokinase
- Other fermentation-derived compounds that vary by preparation
Key point: Natto is the source, a broad nutritional context, not a single ingredient.
2) Nattokinase: one specific enzyme
Nattokinase is an enzyme produced during fermentation. Research has mainly explored it in relation to circulation-related markers, particularly pathways linked to fibrin and clot breakdown, in laboratory and clinical studies.
Key point: Nattokinase is one component associated with natto. It is not the same as eating natto, and it is not a vitamin.
Because it is often sold as a standalone supplement, quality and enzyme activity can vary widely between products.
3) Vitamin K2 (MK-7): a vitamin linked to bone-related calcium handling
Vitamin K2 refers to a group of compounds called menaquinones. MK-7 is one form that natto is especially known for.
Vitamin K (including K2 forms) plays a role in activating certain proteins involved in:
- Normal bone mineralisation
- Calcium handling as part of normal physiology
Key point: MK-7 is a vitamin, not an enzyme, and not interchangeable with nattokinase, even though natto contains both.
Why are these often confused?
Because natto naturally contains both nattokinase and vitamin K2 (MK-7), the terms are often blurred together online. But they serve different roles:
- Want the whole fermented food context? → Natto
- Looking at a specific enzyme studied for circulation markers? → Nattokinase
- Interested in a vitamin linked to bone-related pathways? → Vitamin K2 (MK-7)
Understanding this distinction helps avoid mismatched expectations.
Who should be cautious?
- Vitamin K (including K2) can affect how warfarin and similar anticoagulants are managed. People on these medications are usually advised to maintain a consistent vitamin K intake and to follow clinician guidance.
- Anyone taking blood thinners, antiplatelet medication, or managing clotting or bleeding conditions should be cautious with enzyme- or circulation-focused supplements and seek medical advice first.
Frequently asked questions
Is nattokinase the same as vitamin K2?
No. Nattokinase is an enzyme, while vitamin K2 (MK-7) is a vitamin. They are different compounds with different roles, even though both can be present in natto.
Does eating natto give the same effect as taking nattokinase supplements?
Not necessarily. Natto is a whole fermented food that contains many components, whereas nattokinase supplements usually isolate a single enzyme. The experience and effects may differ.
Why is natto often linked to bone health?
Because natto is a rich dietary source of vitamin K2 (MK-7), which is involved in activating proteins that support normal bone-related calcium handling as part of overall nutrition.
