Nattokinase for Heart Health: Benefits and How It Works

Reviewed by Dr. Thomas Alexander, Chief Medical Officer

Nattokinase is an enzyme with a specific, well-defined origin story — and a growing body of research behind it. Here's what it is and why it's become a popular addition to heart-health routines.

What Is Nattokinase?

Nattokinase is an enzyme extracted from natto, a traditional Japanese fermented soybean dish. It was first identified by a Japanese researcher in the 1980s while screening natural substances for their effect on blood clot dissolution in a lab setting.

How It's Believed to Work

Nattokinase is studied for its potential role in supporting healthy blood flow and the body's natural clot-breakdown processes. This has made it a popular ingredient in cardiovascular-focused supplement routines, particularly among people looking for a plant/fermentation-derived option.

What to Look for in a Nattokinase Supplement

• Standardized activity (FU – Fibrinolytic Units): Look for products that state their potency in FU rather than just milligrams, since this reflects actual enzymatic activity, not just ingredient weight.
• Enteric coating: Because nattokinase is an enzyme, some formulas use enteric coating to help it survive stomach acid and be active where it matters.
• Sourcing transparency: Look for products that reference a specific, standardized production process.

Who Should Be Cautious

Because nattokinase is studied for its effect on clotting, it is not appropriate for anyone on blood-thinning medication, anyone with a bleeding disorder, or anyone scheduled for surgery, without direct physician guidance.

Not medical advice. Nattokinase should not be combined with blood-thinning medication or used before surgery without explicit physician approval.