Does Nattokinase Clean Arteries? Reviewing the Evidence

Nattokinase, an enzyme derived from the Japanese fermented soybean food natto, has gained significant attention for its purported ability to dissolve blood clots and improve arterial health. Here is what the research actually supports.

What Is Nattokinase

Nattokinase is a serine protease enzyme produced during the fermentation of soybeans by Bacillus subtilis natto. It was first identified in 1987 by researcher Hiroyuki Sumi, who observed its ability to dissolve fibrin (the protein framework of blood clots) in laboratory settings.

Fibrinolytic Activity

The most well-documented property is fibrinolysis. In vitro and animal studies consistently show that nattokinase dissolves fibrin. Human trials demonstrate reduced fibrinogen levels and improved blood flow markers. A 2022 meta-analysis of 10 trials found significant reduction in blood pressure.

The Arterial Plaque Question

The claim that nattokinase "cleans arteries" of atherosclerotic plaque is an extrapolation beyond current evidence. Plaque is composed of cholesterol, calcium, and inflammatory cells, not just fibrin. While some preliminary studies suggest reduced plaque progression, reversal has not been demonstrated.

What Studies Actually Show

Reduced blood viscosity, modest blood pressure reduction (5-8 mmHg systolic), improved blood flow in microcirculation, and reduced risk of deep vein thrombosis during long-haul flights.

Safety Considerations

Nattokinase should not be combined with blood-thinning medications without medical supervision. It has anticoagulant properties that could increase bleeding risk. People with clotting disorders or scheduled surgery should avoid it.

Practical Use

Typical supplemental doses are 2000-4000 FU daily. Eating natto directly provides the enzyme plus additional benefits from vitamin K2 (MK-7) and probiotics. Many find the supplement preferable due to natto's challenging taste and texture.