Nattokinase

A fermented-soybean enzyme with real blood pressure trial data and a serious blood-thinner interaction

RCT showed -5.5 mmHg systolic vs. placebo

Requires real caution with blood thinners

Important: These statements have not been evaluated by the FDA. This information is not intended to diagnose, treat, cure, or prevent any disease. Do not combine with blood thinners or antiplatelet medications without your doctor's approval, and stop before any scheduled surgery.

Overview

Nattokinase is an enzyme extracted from natto, a traditional Japanese food made from fermented soybeans. It has a long history of dietary use in Japan and has drawn supplement-world interest for its role in supporting the body's fibrinolytic system — the natural process that breaks down blood clots and helps maintain healthy circulation.

Unlike a lot of trending heart-health ingredients, nattokinase has actual randomized, placebo-controlled human trial data behind it, not just cell-culture or animal research. That real trial evidence is also exactly why it comes with a genuinely serious safety consideration: its effect on clotting pathways means it can interact meaningfully with blood thinners and antiplatelet medications, which is not a minor caution to skip past.

Potential Benefits

Blood Pressure Support

A randomized, placebo-controlled trial found an 8-week course produced a meaningful net reduction in both systolic and diastolic blood pressure.

Fibrinolytic (Clot-Breakdown) Support

Directly breaks down fibrin and activates additional pathways involved in the body's natural clot-dissolving process.

Cardiovascular Risk Marker Research

A meta-analysis of randomized controlled trials found nattokinase supplementation improved several measured cardiovascular risk factors.

Long Dietary History

Derived from natto, a food with a centuries-long history of regular dietary consumption in Japan.

Typical Dosage

Standard Daily Dose

2,000 FU per day

Measured in fibrinolytic units (FU), the dose used in the positive blood pressure trials

Duration to See Effects

8 weeks or more

Matches the trial length that showed a measurable blood pressure reduction

Pro Tips

Never combine with warfarin, aspirin therapy, or other blood thinners without explicit medical approval
Stop taking it at least 1-2 weeks before any scheduled surgery — confirm the exact timing with your surgeon
Look for a product measured in FU (fibrinolytic units), the standard used in the clinical research
Those with a bleeding disorder or upcoming procedures should get direct physician guidance before starting

Research Snapshot

A randomized, double-blind, placebo-controlled trial in 86 adults with systolic blood pressure between 130-159 mmHg found that 2,000 FU/day of nattokinase for 8 weeks produced a net reduction of 5.55 mmHg systolic and 2.84 mmHg diastolic blood pressure compared to placebo. A subsequent systematic review and meta-analysis of randomized controlled trials confirmed nattokinase supplementation significantly reduced both systolic and diastolic blood pressure across the pooled trial data.

Source: Kim et al., Hypertension Research (2008)

How Nattokinase Compares

Ingredient	Best For	Key Difference
Nattokinase	Blood Pressure, Circulation	Real RCT data, but requires blood-thinner caution
Hibiscus	Blood Pressure	Larger meta-analysis base, no comparable clotting interaction
CoQ10	Heart & Energy Support	Different mechanism, commonly recommended alongside statins
Omega-3	Cardiovascular Support	Broader evidence base, also carries a mild bleeding-risk caution at high doses

These are the most common comparisons our customers ask about in-store.

Popular Stacks with Nattokinase

Blood Pressure Support Stack

Nattokinase + Hibiscus + Magnesium

Combines multiple blood-pressure-focused ingredients with different mechanisms

Circulation Support Stack

Nattokinase + CoQ10 + Omega-3

A heart-health-focused combination — discuss with your doctor if also on medication

Healthy Aging Heart Stack

Nattokinase + Hawthorn + Beetroot

Pairs circulation support with traditional cardiovascular botanicals

Frequently Asked Questions

What does nattokinase actually do?

Nattokinase is an enzyme extracted from natto, a traditional Japanese fermented soybean food. It supports the body's natural clot-breakdown (fibrinolytic) system in several ways — directly breaking down fibrin, converting a precursor into active urokinase, and increasing levels of tissue plasminogen activator, all of which contribute to healthy blood flow.

Can nattokinase lower blood pressure?

A randomized, double-blind, placebo-controlled trial in adults with elevated blood pressure found nattokinase supplementation for 8 weeks produced a net reduction of about 5.5 mmHg systolic and 2.8 mmHg diastolic compared to placebo. A more recent systematic review and meta-analysis of randomized controlled trials confirmed nattokinase supplementation significantly reduced both systolic and diastolic blood pressure.

Is nattokinase safe to take with blood thinners?

This is the most important safety consideration with nattokinase. Because it affects the same clot-related pathways as prescription blood thinners and antiplatelet medications, combining them without medical supervision raises real bleeding risk. Anyone on warfarin, aspirin therapy, or other anticoagulants should not start nattokinase without their doctor's explicit approval, and it should be stopped before any scheduled surgery.

Sources & References

1. Kim, J.Y., Gum, S.N., Paik, J.K., et al. (2008). Effects of nattokinase on blood pressure: a randomized, controlled trial. Hypertension Research, 31(8), 1583–1588.

2. Nattokinase supplementation and cardiovascular risk factors: a systematic review and meta-analysis of randomized controlled trials. Systematic Reviews / meta-analysis (2024).

All references are peer-reviewed studies or position stands from reputable organizations.