Does Nattokinase Dissolve Plaque in Arteries?

Almost every article you'll find about nattokinase and arterial plaque leaves out one study — the biggest, longest, and most rigorous one ever done — because its result complicates the marketing story.

The short version: nattokinase's ability to reduce arterial plaque is not settled, and the evidence points in two directions. Human trials at high doses (6,500–10,800 FU/day) have shown carotid plaque reductions of 21.7% to 36% over 6–12 months. A separate 3-year US trial at 2,000 FU/day found no significant difference from placebo. This article walks through what actually happens in your arteries, what the research really shows, and what those numbers mean for you.

Table of Contents

1. What Arterial Plaque Actually Is
2. How Nattokinase Works: Fibrin, Not Plaque
3. Studies Showing Nattokinase Reduces Plaque
4. The Trial That Showed No Effect
5. Why Dose Likely Explains the Contradiction
6. Safety, Interactions, and Who Should Not Take It
7. Matching the Research Dose in a Real Supplement
8. Frequently Asked Questions

1. What Arterial Plaque Actually Is

Atherosclerotic plaque is not a blood clot. It's a slow-growing deposit built into the wall of an artery, made of cholesterol, fat, calcium, and inflammatory cells that accumulates over decades. According to Cleveland Clinic, the complications of that buildup — heart attacks and strokes — are the leading cause of death in the United States, and most people don't know they have plaque until something goes wrong.

The scale is staggering. Atherosclerosis is the underlying driver of approximately 50% of all deaths in industrialized societies, and around 75% of acute myocardial infarctions come from a plaque rupturing rather than gradual narrowing. Ischemic heart disease alone caused 9.0 million deaths worldwide in 2021, per WHO data — roughly 13% of all global fatalities.

This distinction matters for the nattokinase question. A blood clot forms quickly from fibrin, the mesh-like protein your body deploys to stop bleeding. Plaque forms slowly from lipids embedded in the artery wall itself. They are biologically different problems — and any supplement that primarily targets one will not automatically solve the other.

2. How Nattokinase Works: Fibrin, Not Plaque

Nattokinase is a serine protease enzyme extracted from natto — fermented soybeans — with fibrinolytic activity comparable to human plasmin, the body's own primary clot-dissolving protein. According to a 2018 review in Biomarker Insights, it works through three complementary pathways.

First, it directly cleaves fibrin — the protein mesh that gives blood clots their structure — reducing clot mass through a mechanism structurally similar to plasmin. Second, it increases the release of tissue plasminogen activator (tPA), amplifying the body's endogenous clot-clearing signal. Third, it cleaves and inactivates plasminogen activator inhibitor-1 (PAI-1), the main brake on tPA. A 2025 review in Discover Applied Sciences confirmed all three mechanisms.

Notice what's missing: none of these actions targets the cholesterol and inflammatory cells that make up plaque. Nattokinase's core biology is about fibrin, not lipid deposits. So how could it possibly affect plaque? The likely answer is indirect — through improvements in lipid profile, blood pressure, and blood viscosity that together slow plaque progression over time. This is the mechanism proposed in the human trials that showed a plaque effect, and it fits with nattokinase's documented blood pressure reduction of roughly 5 mmHg systolic in the Kim 2008 RCT.

3. Studies Showing Nattokinase Reduces Plaque

Two human studies are the foundation of every "nattokinase dissolves plaque" claim you'll read online. Both are worth understanding in detail — and both used doses substantially higher than the 2,000 FU commonly sold.

The first is Ren et al. 2017, a randomized trial in 82 patients with carotid atherosclerosis and hyperlipidemia, published in Zhonghua Yi Xue Za Zhi. Participants took 6,500 FU/day of nattokinase for 26 weeks. Common carotid artery intima-media thickness dropped 10.6% (from 1.13 mm to 1.01 mm), and carotid plaque size fell by 36.6% (from 0.25 cm² to 0.16 cm²). Head-to-head, this outperformed simvastatin 20 mg/day — the comparator arm — which achieved an 11.5% plaque reduction over the same period.

The second is Chen et al. 2022, a much larger observational study of 1,062 participants aged 63 to 85 with mild atherosclerosis and hyperlipidemia, published in Frontiers in Cardiovascular Medicine. High-dose nattokinase at 10,800 FU/day for 12 months reduced carotid plaque area by 36% and intima-media thickness by 21.7%, alongside significant improvements in LDL cholesterol, triglycerides, and HDL. This is the largest positive dataset in the nattokinase-plaque literature.

Both are meaningful results. Both have caveats. The Ren study was published in a Chinese-language medical journal, the sample size was modest, and it has not been independently replicated in a Western clinical setting. The Chen 2022 study, while large, was observational rather than a blinded randomized trial — a lower tier of evidence. Neither has been replicated at scale in a US or European academic center. That is not a reason to dismiss them, but it is the honest context.

4. The Trial That Showed No Effect

The single most rigorous study of nattokinase and carotid atherosclerosis is one most supplement pages never mention. The Nattokinase Atherothrombotic Prevention Study (NAPS), published in 2021 in Clinical Hemorheology and Microcirculation, was conducted at the Keck School of Medicine at USC.

The design: 265 healthy adults with median age 65.3, no clinical evidence of cardiovascular disease, randomized to 2,000 FU/day of nattokinase or matching placebo, for a median of 3 years. Primary outcomes were carotid artery intima-media thickness (CIMT) and carotid arterial stiffness, measured by serial ultrasound every 6 months.

The result: no statistically significant difference between the nattokinase and placebo groups. The annualized rate of change in both CIMT and arterial stiffness was essentially the same in both arms of the trial. In healthy older adults taking the widely marketed 2,000 FU dose, nattokinase did not slow the progression of subclinical atherosclerosis in a 3-year timeframe. This is one of only a handful of long-term US academic trials on the enzyme, and its scale and blinding put it above every positive study on methodological grounds.

NAPS does not prove nattokinase never affects plaque — Ren 2017 and Chen 2022 are still on the table. But NAPS does suggest that at 2,000 FU/day, in healthy people without existing atherosclerosis, over 3 years, there is no measurable plaque-slowing effect. That is a narrower claim than "nattokinase doesn't work," but it's the claim the evidence supports.

5. Why Dose Likely Explains the Contradiction

Look at the dosing across the three main studies and a pattern emerges. Ren 2017: 6,500 FU/day. Chen 2022: 10,800 FU/day. NAPS 2021: 2,000 FU/day. The two studies showing plaque reduction used 3–5x more nattokinase than the study that showed no effect.

The population matters too. Ren and Chen enrolled participants who already had atherosclerosis and hyperlipidemia — active disease with measurable plaque and lipid abnormalities. NAPS enrolled healthy older adults without clinical CVD. Healthy participants have less plaque to reduce and more variability in progression, so both directions of effect are diluted. This is a recurring pattern in supplement science: measurable benefits show up in people with the target condition, not in generally healthy adults taking a preventive dose.

The practical takeaway is more nuanced than "nattokinase dissolves plaque" or "nattokinase does nothing." At the 2,000 FU dose used in the widely cited blood pressure RCT by Kim et al., the evidence supports a modest blood pressure benefit (~5 mmHg systolic) and fibrinolytic activity — but not documented plaque reduction. To see the plaque-related outcomes reported in Ren and Chen, you would likely need 3–5x more nattokinase over 6–12 months, in a person who already has atherosclerosis, ideally under physician supervision. The full dosage range across the clinical literature is covered in more detail here.

6. Safety, Interactions, and Who Should Not Take It

Nattokinase's fibrinolytic activity — the reason it's interesting for cardiovascular support — is also the reason it carries real bleeding risk in specific populations. According to Memorial Sloan Kettering's supplement monograph, nattokinase may theoretically increase bleeding risk when combined with anticoagulants (warfarin, apixaban, rivaroxaban), antiplatelet drugs (aspirin, clopidogrel), or thrombolytic medications.

The Drugs.com professional monograph documents that short-term trials have reported no adverse reactions, but there is at least one case report of acute cerebellar hemorrhage in a patient with a history of ischemic stroke who took nattokinase. Case reports are not a basis for population risk estimates, but they establish that serious bleeding events are biologically possible. A separate case report of mechanical heart valve thrombosis in a patient who substituted nattokinase for warfarin makes the reverse point equally clearly: nattokinase is not a replacement for prescribed anticoagulation.

Safety data is also lacking for pregnancy and lactation, so avoidance during those periods is the standard clinical position. People with active bleeding, recent hemorrhagic stroke, bleeding disorders, or severe liver disease should not take nattokinase, and anyone on prescription blood thinners must speak to their doctor before adding it — the interaction picture is covered in more depth in the natural blood thinner article. For most healthy adults not on cardiovascular medications, nattokinase at 2,000 FU/day has a strong short-term safety record across the published clinical trials to date.

7. Matching the Research Dose in a Real Supplement

Choosing a nattokinase supplement is largely a question of matching the dose used in the studies that align with your goal. For general fibrinolytic activity and mild blood pressure support, the 2,000 FU/day dose used in the Kim 2008 hypertension trial is the best-evidenced starting point. It's also the dose in the NAPS trial — meaning short-term fibrinolytic and blood pressure effects are documented, even though plaque-slowing effects at that dose are not.

BioAbsorb Nattokinase Enzyme delivers exactly this dose: 100 mg of nattokinase per capsule providing 2,000 FU of fibrinolytic activity, one capsule daily. Two formulation choices are worth flagging. First, the product uses DRcaps delayed-release veggie capsules — a plant-based capsule technology that resists stomach acid and delivers the enzyme intact to the small intestine, without the phthalates and plasticizers found in some enteric-coated alternatives. Nattokinase is inactivated below pH 3, so how it's delivered matters as much as the dose.

Second, the formulation is intentionally free of Vitamin K2. Natto naturally contains high K2, which can interfere with warfarin — removing it makes the product cleaner for anyone managing K2 intake separately or taking anticoagulant medications. The 60-capsule bottle is a full 60-day supply at one capsule daily, and every batch is third-party tested for enzyme activity (≥2,000 FU per capsule), heavy metals, and microbial contaminants at a GMP-certified Canadian facility. For readers who want to explore how nattokinase compares to the other main systemic enzyme, serrapeptase, the comparison article covers both.

Frequently Asked Questions

Does nattokinase dissolve plaque in arteries?

Not directly. Nattokinase dissolves fibrin, the protein mesh in blood clots — not the cholesterol-based plaque built into artery walls. Two clinical studies at high doses (6,500 and 10,800 FU/day) reported carotid plaque reductions of 22–36% in people with existing atherosclerosis, but a 3-year US trial at 2,000 FU/day in healthy older adults found no significant plaque effect.

How long does it take nattokinase to reduce plaque?

The two studies showing plaque reduction ran for 6 months (Ren 2017) and 12 months (Chen 2022). Shorter timeframes have not documented plaque changes in clinical trials. Any plaque effect appears to require sustained supplementation for at least 6 months at doses well above the standard 2,000 FU/day.

What dose of nattokinase is needed for plaque reduction?

The Ren 2017 study used 6,500 FU/day; Chen 2022 used 10,800 FU/day. Neither dose is the same as the 2,000 FU used in the largest blood pressure trial. Higher doses have shown plaque effects only in people who already had atherosclerosis — this is not a self-directed dosing decision and should be made with a physician.

Can nattokinase replace a statin for heart disease?

No — and no responsible clinician would recommend that substitution. In the Ren 2017 head-to-head, nattokinase 6,500 FU outperformed simvastatin on plaque reduction, but statins have decades of large-scale randomized outcome data on heart attacks, strokes, and death that nattokinase does not. The 2,000 FU dose most people buy has never been shown to reduce plaque at all.

Is nattokinase safe if I'm on blood thinners?

Not without medical supervision. Nattokinase and drugs like warfarin, apixaban, or aspirin have overlapping mechanisms that can additively increase bleeding risk, per institutional guidance from Memorial Sloan Kettering. Case reports of serious bleeding events exist. This is a conversation to have with your prescriber before starting, not after.

What's the difference between fibrin and arterial plaque?

Fibrin is a stringy protein your body deploys within seconds to form blood clots when a vessel is injured. Arterial plaque is a slow-growing deposit of cholesterol, calcium, and inflammatory cells built into the artery wall over decades. Nattokinase acts on fibrin directly and on plaque only indirectly — through modest improvements in blood pressure, lipids, and viscosity that may slow plaque progression over time.

Conclusion

The honest answer to "does nattokinase dissolve plaque in arteries" is: at high doses in people with existing atherosclerosis, two clinical studies suggest it may reduce plaque by 22–36% over 6–12 months, but the largest 3-year trial at the widely sold 2,000 FU dose found no effect. If you want to explore nattokinase for cardiovascular support with realistic expectations, BioAbsorb Nattokinase Enzyme delivers the clinically studied 2,000 FU dose in a delayed-release capsule — and if you're on blood thinners or have cardiovascular disease, talk to your doctor first.

Research References

1. Effective management of atherosclerosis progress and hyperlipidemia with nattokinase: A clinical study with 1,062 participants (Chen H, et al.). Frontiers in Cardiovascular Medicine, Vol. 9 (2022). Reported that 10,800 FU/day nattokinase for 12 months reduced carotid plaque area 36% and intima-media thickness 21.7% in older adults with mild atherosclerosis.
2. A clinical study on the effect of nattokinase on carotid artery atherosclerosis and hyperlipidaemia (Ren NN, et al.). Zhonghua Yi Xue Za Zhi, Vol. 97, Issue 26 (2017). RCT in 82 patients; 6,500 FU/day for 26 weeks reduced carotid IMT 10.6% and plaque size 36.6%, outperforming simvastatin 20 mg/day.
3. Nattokinase atherothrombotic prevention study: A randomized controlled trial (Hodis HN, et al.). Clinical Hemorheology and Microcirculation, Vol. 78, Issue 3 (2021). Double-blinded 3-year RCT in 265 healthy adults; 2,000 FU/day nattokinase produced no significant change in carotid IMT or arterial stiffness vs placebo.
4. Nattokinase: A Promising Alternative in Prevention and Treatment of Cardiovascular Diseases (Chen H, et al.). Biomarker Insights, Vol. 13 (2018). Mechanistic review documenting fibrin cleavage, tPA release, and PAI-1 inactivation as the three fibrinolytic pathways of nattokinase.
5. Effects of Nattokinase on Blood Pressure: A Randomized, Controlled Trial (Kim JY, et al.). Hypertension Research, Vol. 31, Issue 8 (2008). 8-week RCT in 73 adults with pre/stage-1 hypertension; 2,000 FU/day reduced systolic BP by 5.55 mmHg and diastolic by 2.84 mmHg vs placebo.
6. Insights on the therapeutic potential of fibrinolytic enzymes, emphasis on Nattokinase and its enhanced production using advanced technologies: a critical review. Discover Applied Sciences (Springer Nature), Vol. 7 (2025). Recent synthesis confirming direct fibrin hydrolysis, plasmin-like activity, and cardiovascular relevance.
7. Atherosclerosis — StatPearls. National Library of Medicine / NCBI Bookshelf (2024 update). Clinical reference: atherosclerosis underlies ~50% of deaths in industrialized society; ~75% of acute MIs from plaque rupture.
8. Heart Disease Facts. U.S. Centers for Disease Control and Prevention (2026). Heart disease is the leading cause of death for most US racial/ethnic groups; hypertension, cholesterol, and smoking are the key modifiable risk factors.
9. Atherosclerosis: Symptoms, Causes & Treatment. Cleveland Clinic (2025). Patient-facing reference: plaque buildup complications (heart attack, stroke) are the leading US cause of death.
10. Atherosclerosis — Merck Manual Professional Edition (2026). WHO data: ischemic heart disease accounted for ~13% of all global deaths from 2000–2021 (9.0 million deaths in 2021).
11. Nattokinase — About Herbs, Botanicals & Other Products. Memorial Sloan Kettering Cancer Center Integrative Medicine Service. Theoretically increases bleeding risk with anticoagulants, antiplatelets, or fibrinolytic drugs; safety in pregnancy/lactation not established.
12. Nattokinase — Professional Monograph. Drugs.com (2026). Documented case report of acute cerebellar hemorrhage in a nattokinase user with ischemic stroke history; small trials otherwise report no adverse reactions.

About the Author

David Kimbell is a health writer, digital entrepreneur and former aerospace engineer, based in Ottawa, Canada. He loves translating complex science into clear, actionable guidance for consumers seeking evidence-based solutions.

---

Important Disclaimers

Medical Disclaimer: This article provides educational information only and is not intended as medical advice. Always consult with a qualified healthcare provider before starting any new supplement, especially if you have existing health conditions, take medications, or are pregnant or nursing.

FDA/Health Canada Statement: These statements have not been evaluated by the Food and Drug Administration or Health Canada. This product is not intended to diagnose, treat, cure, or prevent any disease.