Nattokinase vs Serrapeptase: What Is the Difference?

Nattokinase and serrapeptase are both protein-digesting enzymes sold as supplements, and both are often described as breaking down fibrin. They come from different bacteria, are measured in different units and have been studied for different things. Nattokinase comes from natto, a fermented soybean food, and most of its research looks at blood clotting markers. Serrapeptase comes from Serratia bacteria and has mainly been studied for swelling and pain after surgery. This guide compares the two side by side, explains what the evidence shows, and covers whether you can take them together.

What is nattokinase?

Nattokinase is an enzyme made by the bacterium Bacillus subtilis var. natto when it ferments soybeans into natto, a traditional Japanese food. It breaks down fibrin, a protein involved in blood clotting (Weng et al., 2017). In supplements, its strength is given in fibrinolytic units (FU), which measure its activity rather than its weight. Our nattokinase capsules provide 6,000 FU each. To learn more about the food itself, read our guide to nattokinase foods and natto.

What is serrapeptase?

Serrapeptase, also called serratiopeptidase, is a protein-digesting enzyme made by Serratia bacteria. In some countries it is prescribed by surgeons, dentists and ear, nose and throat specialists for swelling and pain, and it has also been suggested to act on fibrin (Bhagat et al., 2013). In the UK it is sold as a food supplement, usually in capsules labelled with serrapeptase units rather than milligrams. Because stomach acid can damage it, it is often sold in enteric-coated capsules.

Nattokinase vs serrapeptase: side-by-side comparison

What the evidence shows

Nattokinase research

A small placebo-controlled study found that a single 2,000 FU dose of nattokinase raised markers of fibrin breakdown and lengthened a clotting time test over the next few hours in healthy young men, although all results stayed within the normal range (Kurosawa et al., 2015). The longest trial gave 265 healthy older adults 2,000 FU a day or a placebo for a median of 3 years. It found no difference in the thickening or stiffness of the neck arteries, and no significant effect on blood pressure or any laboratory measure (Hodis et al., 2021). So nattokinase does act on clotting markers in the short term, but a long-term benefit has not been shown.

Serrapeptase research

A 2013 systematic review found 24 studies on serrapeptase. The reviewers concluded that the evidence for its use as an anti-inflammatory and painkiller comes from studies of poor methodology, mostly small and placebo-controlled, that dose and duration were often not stated, and that data on its safety and tolerability were lacking (Bhagat et al., 2013). Claims that serrapeptase clears arteries are based on anecdotal reports, not on trials.

Side effects and safety

Both enzymes may affect how the blood clots, so the main caution is the same for both: they are not suitable for people who take anticoagulants such as warfarin, apixaban or rivaroxaban, antiplatelets such as aspirin or clopidogrel, or who have a bleeding disorder, unless a doctor agrees. Stop either one at least 2 weeks before surgery or dental treatment.

• Nattokinase: generally well tolerated in studies. There is one case report of a brain bleed in a man who took nattokinase with aspirin. Nattokinase comes from soy, so avoid it if you are allergic to soya. Our capsules are vitamin K2-free. Read our full guide to nattokinase side effects.
• Serrapeptase: there is less safety information, because the systematic review found little safety data in the trials. Ask a pharmacist before taking it, especially with other medicines.

Can you take nattokinase and serrapeptase together?

No studies have tested nattokinase and serrapeptase together, so nobody knows whether their effects on clotting add up, or by how much. Because both may affect bleeding, we do not recommend combining them, or adding a third enzyme such as lumbrokinase. If you are already taking one and want to try the other, speak to your GP or pharmacist first, and do not take both at the same time without their advice.

Nattokinase or serrapeptase: which one should you choose?

They are not interchangeable. If your interest is in the enzyme from natto and the research on clotting markers, nattokinase is the better studied of the two, with toxicology data and a 3-year trial behind it. If you have been told about serrapeptase for swelling after an operation or dental work, ask the clinician treating you, because that use is a medical one and the supplement evidence is weak.

Whichever you consider, check the strength on the label (FU for nattokinase), stick to the stated daily amount, and speak to your GP or pharmacist first if you take any regular medicine. For how and when to take nattokinase, see our nattokinase dosage guide and best time to take nattokinase. For another enzyme comparison, read lumbrokinase vs nattokinase.

The bottom line

Nattokinase and serrapeptase are both protein-digesting enzymes, but they come from different bacteria and have been studied for different reasons. Nattokinase has the stronger research base and is the enzyme found in natto. The serrapeptase studies are small and of poor quality. Both may affect bleeding, neither should be taken with blood thinners unless a doctor agrees, and they should not be combined.

Nattokinase 6000 FU Capsules — NutritionGo

6,000 FU per capsule · Vitamin K2-free · Vegan HPMC capsules

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References

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