What Is Nattokinase? Benefits, Research & Who Should Avoid It

What is Nattokinase?

Nattokinase is a potent enzyme extracted from natto, a traditional Japanese dish made from fermented soybeans. This dish has been consumed for centuries for its cardiovascular benefits, particularly in Japanese cultures with high longevity rates. The enzyme is produced during the fermentation process by the bacterium Bacillus subtilis.

Unlike many compounds that require complex synthesis, nattokinase is naturally derived and biologically active. It has gained attention in nutritional science for its fibrinolytic properties—that is, its ability to break down fibrin, a protein involved in blood clot formation. This action supports healthy blood flow and cardiovascular function.

How Nattokinase Works

Fibrin is essential in wound healing and clot formation, but excess fibrin in the bloodstream can contribute to reduced circulation. Nattokinase supports the body’s natural ability to manage fibrin levels by:

• Breaking down existing fibrin deposits
• Supporting the body’s fibrinolytic (clot-dissolving) system
• Activating plasminogen, which converts to plasmin, a key enzyme in clot breakdown

This mechanism positions nattokinase as a unique dietary enzyme with circulatory support potential.

What the research says-

1. Supports Healthy Blood Pressure

Several clinical trials suggest nattokinase may help maintain healthy blood pressure levels. A notable 8-week study involving adults with prehypertension or mild hypertension found that daily supplementation with 2,000 FU (fibrinolytic units) of nattokinase helped reduce systolic and diastolic pressure by modest yet statistically significant margins.

These effects are thought to result from improved blood flow and decreased blood viscosity, factors that influence vascular resistance.

2. Encourages Circulatory Health

The primary claim to fame for nattokinase is its support for healthy circulation. By naturally breaking down excess fibrin, the enzyme can promote smoother blood flow. This is particularly relevant for people looking to support vein and artery health as part of a heart-conscious lifestyle.

While not a substitute for medical treatment, nattokinase may complement dietary patterns aimed at optimising vascular health.

3. Cholesterol Modulation Potential

Emerging data suggest that nattokinase may influence lipid profiles. Some preliminary studies report slight improvements in HDL (good cholesterol) and reductions in LDL (bad cholesterol), although findings remain inconsistent and require more robust trials.

For now, this benefit remains promising but unconfirmed.

Who Should Avoid Nattokinase?

Because of its fibrinolytic action, nattokinase is not suitable for everyone. You should avoid or use with caution if:

• You are taking anticoagulants (e.g., warfarin, aspirin, or clopidogrel)
• You have a bleeding disorder or upcoming surgery
• You are pregnant or breastfeeding
• You have recently experienced a serious injury or hemorrhage

Always consult a healthcare provider before starting nattokinase, especially if you take medications affecting blood clotting or circulation.