Nattokinase

Also known as: nattokinase, subtilisin NAT, NSK-SD, natto-derived protease

Grade B — Moderate Evidenceenzymeheartcirculation
2000–4000 FU (fibrinolytic units)Empty stomach for maximum fibrinolytic activity. Morning or evening.

Nattokinase is a fibrinolytic enzyme derived from natto (fermented soybeans) that directly degrades fibrin, the structural protein in blood clots. Clinical trials demonstrate reductions in blood pressure, improved blood viscosity, and decreased fibrinogen levels. It is used widely in Japan for cardiovascular prevention and has a strong safety profile at doses of 2,000-4,000 FU/day, though it should be used cautiously alongside anticoagulant medications.

TL;DR: Direct fibrinolytic enzyme from natto. Reduces blood pressure and DVT risk. Use with extreme caution regarding bleeding.

❤️Heart Health
Last reviewed: 2026-03-12

Quick Facts

Evidence

Grade B

Studies

2

Interactions

3

Forms

1

Evidence Rating: Grade B — Moderate Evidence

Some RCTs with positive results, or strong observational evidence. More research may refine our understanding.

Interaction Warnings

Warfarin / anticoagulantsHigh Risk

SIGNIFICANT — direct fibrinolytic; serious bleeding risk; avoid without physician oversight

Thrombolytics (tPA)High Risk

Additive; avoid combination

Aspirin / NSAIDsModerate

Additive antiplatelet; monitor

Important Notes

  • ⚠️ BLEEDING RISK — direct fibrinolytic enzyme
  • CONTRAINDICATED with anticoagulants without supervision
  • Stop 2 weeks before surgery
  • CONTRAINDICATED in active bleeding or hemorrhagic stroke

Clinical Evidence (2 studies)

Nattokinase reduced blood pressure

Kim JY et al. (2008) — Nutrition

Significantly reduced BP and improved lipid markers in hypertensive subjects; RCT

View on PubMed

Nattokinase reduced venous thrombus in air travel

Cesarone MR et al. (2003) — Angiology

Reduced venous thrombus formation in long-haul travel vs placebo; RCT

View on PubMed

Alternatives to Consider

These supplements target similar goals and may be worth considering alongside or instead of Nattokinase.

Garlic / Allicin

Grade A

Strong RCT evidence for blood pressure reduction (~8-9/5-6 mmHg) and cold prevention (64% reduction). Aged extract preferred for CV.

❤️ Heart Health

Red Yeast Rice

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Natural statin alternative with 15-25% LDL reduction. 45% coronary event reduction in large RCT. MUST co-supplement CoQ10.

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Ginkgo Biloba

Grade B

Increases cerebral blood flow and has vasodilatory effects. Modest benefit for existing dementia symptoms but does not prevent it.

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Beta-Glucan

Grade B — Moderate Evidence

Dual-purpose supplement: yeast-derived for immune support (250mg), oat-derived for cholesterol (3g). Both well-supported by RCTs.

Garlic / Allicin

Grade A — Strong Evidence

Strong RCT evidence for blood pressure reduction (~8-9/5-6 mmHg) and cold prevention (64% reduction). Aged extract preferred for CV.

Bergamot

Grade B — Moderate Evidence

Impressive lipid-modifying polyphenol: 30% LDL reduction in RCTs. Natural HMG-CoA reductase inhibitor (statin-like mechanism).

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⚕️ Important Disclaimer

This information is for educational purposes only. It is not medical advice. Always consult a healthcare provider before starting any supplement regimen, especially if you take medications or have health conditions.

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