Nattokinase vs Serrapeptase: What’s the Difference? (2026)

At a Glance

• Both are enzymes, used for different things Nattokinase is sold mainly for circulation and blood pressure; serrapeptase mainly for swelling and inflammation.
• Nattokinase evidence Modest blood pressure drops in short trials¹ and changes in clotting tests³, but no effect in a 3-year trial².
• Serrapeptase evidence Small trials found less swelling and jaw stiffness after wisdom tooth surgery⁵⁶, but a systematic review called the overall evidence poor quality⁷.
• No head-to-head trials We found no study comparing the two.
• Top pick Nutricost Nattokinase 2,000 FU – the #1 pick in our guide to the best nattokinase supplements: one capsule a day at the 2,000 FU dose used in most trials.

The Short Answer: Nattokinase and serrapeptase are both protein-digesting enzymes, but they’re studied for different problems. Nattokinase has the more relevant human data for heart and circulation, including a meta-analysis on blood pressure¹ and a 3-year trial that found no effect². Serrapeptase’s best evidence is for reducing swelling and jaw stiffness after wisdom tooth removal⁵⁶.

On this page

1. Nattokinase vs Serrapeptase at a Glance
2. Nattokinase: What the Research Shows
3. Serrapeptase: What the Research Shows
4. Can You Take Nattokinase and Serrapeptase Together?
5. Which One Fits Your Goal?
6. Final Verdict
7. Frequently Asked Questions

Neither is proven to dissolve clots, clear arteries or treat chronic inflammation. If circulation is your goal, nattokinase is the better-studied choice; compare products in our guide to the best nattokinase supplements. If you’re looking at serrapeptase, see our guide to the best serrapeptase supplements.

Nattokinase vs Serrapeptase at a Glance

	Nattokinase	Serrapeptase
Source	Made during fermentation of soybeans into natto4	Made by Serratia bacteria
Label units	FU (fibrinolytic units)	SPU (serrapeptase units) or mg
Main marketed use	Circulation, blood pressure, clots	Swelling, pain, inflammation, mucus
Best human evidence	About 3.5/2.3 mmHg lower blood pressure in 6 trials1	Less swelling and jaw stiffness after wisdom tooth surgery56
Longest trial	3 years, no effect on arteries or blood pressure2	Mostly days to weeks57
Bleeding concern	Yes; MSK advises avoiding with blood thinners4	Little data
Overall evidence	Mixed	Weak7

Nattokinase: What the Research Shows

Nattokinase is the more studied of the two for heart health:

• Blood pressure: A 2023 meta-analysis of 6 trials found an average drop of about 3.5/2.3 mmHg¹.
• Arteries: In the 3-year NAPS trial of 265 adults, 2,000 FU a day didn’t slow artery thickening or change blood pressure².
• Clotting: It lengthened clotting tests compared with placebo³.

For more, see our guide to nattokinase benefits.

Serrapeptase: What the Research Shows

Most serrapeptase trials are small and short:

• Wisdom tooth surgery: In a trial of 133 patients, serrapeptase reduced cheek swelling and improved jaw opening by day 4 compared with control, though pain wasn’t different⁵. A meta-analysis of 5 studies found it improved jaw stiffness more than corticosteroids, with no difference in swelling⁶.
• Airway mucus: In an open-label study in people with chronic airway disease, 4 weeks of serrapeptase reduced sputum thickness and coughing⁹. There was no placebo group.
• Overall quality: A systematic review concluded that the evidence for serrapeptase as an anti-inflammatory or painkiller comes from studies with poor methodology, and that safety data are lacking⁷.

We didn’t find human trials of serrapeptase for blood clots, circulation or heart health.

Our Top Nattokinase Pick

Nutricost Nattokinase 2,000 FU

2,000 FU1 capsule a day120 servings

If circulation or blood pressure is your goal, nattokinase is the better-studied enzyme, and Nutricost gives the 2,000 FU dose used in most trials in one capsule. It’s the #1 pick in our guide to the best nattokinase supplements. It hasn’t been tested in its own clinical trial, and it isn’t suitable if you take aspirin or a blood thinner.

Check price on Amazon → See all 7 picks

Can You Take Nattokinase and Serrapeptase Together?

There are no studies of the two taken together. Both are protein-digesting enzymes, and nattokinase affects clotting³, so combining them adds uncertainty. If you take a blood thinner or daily aspirin, MSK advises not using nattokinase at all⁴, and there’s too little data on serrapeptase to call it safe with these medicines.

These supplements are meant to be swallowed. In one case report, a man injected an oral serrapeptase and nattokinase product into a vein and needed his arm amputated⁸.

See our guides to nattokinase side effects and nattokinase and blood thinners.

Which One Fits Your Goal?

Your goal	Better-studied choice	Notes
Blood pressure	Nattokinase	Small effect in short trials; none over 3 years12
Circulation or clotting markers	Nattokinase	Changes clotting tests3; not proven to prevent clots
Swelling after dental surgery	Serrapeptase	Small trials only56; ask your dentist
Chronic inflammation or pain	Neither	Evidence is weak for both7

Final Verdict

Nattokinase and serrapeptase are different enzymes with different evidence. Nattokinase has modest, mixed data for blood pressure and clear effects on clotting tests, which also make it risky with blood thinners. Serrapeptase’s best data are for swelling after wisdom tooth surgery, and the overall research is weak. Neither has been compared directly with the other.

If circulation is your goal and you aren’t on blood thinners, a 2,000 FU nattokinase such as Nutricost Nattokinase 2,000 FU matches the studied dose. Compare all 7 picks in our guide to the best nattokinase supplements, and see our nattokinase dosage guide before you start.

Important: This guide is for general information and isn’t medical advice. Don’t take either enzyme with blood thinners or daily aspirin without your doctor’s approval, and never inject a supplement meant to be swallowed.

Frequently Asked Questions

Sources & History9 sources · updated November 11, 2026

References

1. Nattokinase Supplementation and Cardiovascular Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials — Reviews in Cardiovascular Medicine, 2023
2. Nattokinase Atherothrombotic Prevention Study: A Randomized Controlled Trial — Clinical Hemorheology and Microcirculation, 2021
3. The Effects of Nattokinase Supplementation on Collagen-Epinephrine Closure Time, Prothrombin Time and Activated Partial Thromboplastin Time in Nondiabetic and Hypercholesterolemic Subjects — Food & Function, 2019
4. Nattokinase — Memorial Sloan Kettering Cancer Center, About Herbs, 2025
5. Efficacy of Serratiopeptidase After Impacted Third Molar Surgery: A Randomized Controlled Clinical Trial — BMC Oral Health, 2021
6. Role of Serratiopeptidase After Surgical Removal of Impacted Molar: A Systematic Review and Meta-Analysis — Journal of Maxillofacial and Oral Surgery, 2018
7. Serratiopeptidase: A Systematic Review of the Existing Evidence — International Journal of Surgery, 2013
8. Vascular Necrosis of the Upper Extremity After Self-Treatment for Peyronie’s Disease — Sexual Medicine, 2021
9. Effect of the Proteolytic Enzyme Serrapeptase in Patients With Chronic Airway Disease — Respirology, 2003

Update history

• November 11, 2026Rewritten with a side-by-side comparison table, human trial evidence for each enzyme, a case report on injecting an oral enzyme product, and guidance on taking them together.