Nattokinase Supplements: Benefits, Safety, and Heart Health Support

What Is Nattokinase?

Nattokinase is a remarkable enzyme derived from natto, a traditional Japanese fermented food. Natto is created by introducing the bacterium Bacillus subtilis to boiled soybeans. This bacterium produces nattokinase as it breaks down the proteins in the soybeans during fermentation.

Nattokinase was first identified by Dr. Hiroyuki Sumi in 1980 while he was studying at Chicago University. Dr. Sumi was familiar with the data showing from Japan showing natto consumption was linked to heart health benefits. So, he put some natto in a Petri dish containing a large blood clot and found the clot was completely dissolved within 18 hours. This clot-busting effect was far more powerful than anything else he had studied. Dr. Sumi then isolated and determined that nattokinase was the factor in natto responsible for the clot-busting action. 

While natto is a food source of nattokinase, the enzyme is also available as a dietary supplement. Significant research shows that nattokinase supplements are just as safe and effective as consuming natto in providing heart health benefits.^1,2

Nattokinase Supplement Benefits

Heart Health

Nattokinase is known for aiding protein digestion but is also highly valued for its potent “clot-busting” properties. It works by breaking down fibrinogen, a key component in blood clots and atherosclerotic plaque, making it a powerful tool for supporting cardiovascular health.¹ 

Elevated fibrinogen levels are a significant risk factor for cardiovascular disease. Research shows that fibrinogen has a stronger link to cardiovascular mortality than cholesterol, highlighting its critical role in heart health.

Even a single dosage of nattokinase has been shown to produce favorable effects on blood measurements of blood clotting activity.⁴ Other cardiovascular benefits include the ability to:

• Dissolves excess fibrin in blood vessels which improves circulation, causes clot dissolution, and reduces the risk of severe clotting.⁵
• Reduces blood viscosity, improves blood flow, and lowers blood pressure.⁶

The ability to improve blood vessel health was obvious from the results in a human double-blind clinical study 6 In the study, 73 subjects with poor vascular health noted by moderate high blood pressure readings of 130-159/100-120 mm Hg were randomized to take either nattokinase (2000 FU/capsule per day) or a placebo. At the end of 8 weeks, subjects in the nattokinase-supplemented group showed a significant reduction in systolic blood pressure (5.5 mm Hg) and diastolic blood pressure (2.84 mm Hg), compared to subjects in the placebo group. Rather than a direct anti-hypertensive effect, the improvements in blood pressure readings were thought to be a result of improved structure and function of the blood vessels.

Promotes Healthy Airways

Nattokinase’s benefits go beyond the cardiovascular system, as excessive fibrin formation is linked to many health conditions. Researchers at Fukai University in Japan studied its potential in chronic inflammation of the nasal and sinus airways, which can lead to polyps.

Researchers found that nattokinase effectively dissolved polyp tissue in inflamed airways by breaking down its fibrin structure. They also noted reduced viscosity in nasal discharge and sputum from subjects with nasal polyps.

 The elasticity and fluidity of respiratory tract secretions are essential for healthy nasal passages, sinuses, and airways. Thick, viscous mucus can lead to inflammation, blocked airways, polyps, and breathing difficulties. Nattokinase has been shown to improve these secretions, promoting easier breathing, similar to other protease enzymes like bromelain and serrapeptidase.

Lowers Inflammation

Nattokinase, similar to bromelain and serrapeptidase, may aid recovery from sports injuries, surgeries, and physical injuries. It works by breaking down fibrin, improving blood flow, which enhances oxygen and nutrient delivery for healing while removing waste that causes inflammation. This supports recovery and overall health. Nattokinase also shows antioxidant and anti-inflammatory properties. 

Human clinical studies are needed to confirm these benefits.

Breaks Down Amyloid

Amyloid is an abnormal protein that can build up in tissues and organs, disrupting cellular function. Its misfolded structure makes it insoluble and resistant to degradation, allowing it to accumulate and gradually impair normal tissue activity. Amyloid buildup is a key feature of degenerative brain diseases like Alzheimer’s and Parkinson’s, as well as amyloidosis, where deposits can affect the heart, kidneys, liver, and nerves.

Nattokinase has shown the ability to break down amyloid in lab studies, but human clinical trials are needed to confirm this effect in the body.

Are Nattokinase Supplements Safe?

While nattokinase has been shown to be very safe, especially at the typical dosage of 100 mg supplying 2,000 Fibrinolytic units once or twice daily, there are some important drug interactions to be aware of. Nattokinase should not be used with Coumadin unless closely monitored by a physician. Also, nattokinase may increase bleeding tendencies when combined with anti-platelet drugs (including aspirin, but especially drugs like clopidogrel, prasugrel, dipyridamole, etc.). If you are taking these sorts of medications, please consult with your healthcare provider before taking nattokinase.

References:

1. Granito M, Alvarenga L, Ribeiro M, et al. Nattokinase as an adjuvant therapeutic strategy for non-communicable diseases: a review of fibrinolytic, antithrombotic, anti-inflammatory, and antioxidant effects. Expert Rev Cardiovasc Ther. 2024 Oct;22(10):565-574.
2. Gallelli G, Di Mizio G, Palleria C, et al. Data Recorded in Real Life Support the Safety of Nattokinase in Patients with Vascular Diseases. Nutrients. 2021 Jun 13;13(6):2031. 
3. Weng Y, Yao J, Sparks S, Wang KY. Nattokinase: An Oral Antithrombotic Agent for the Prevention of Cardiovascular Disease. Int J Mol Sci. 2017 Feb 28;18(3):523. 
4. Kurosawa Y, Nirengi S, Homma T, et al. A single-dose of oral nattokinase potentiates thrombolysis and anti-coagulation profiles. Sci Rep. 2015 Jun 25;5:11601.
5. Hsia CH, Shen MC, Lin JS, et al. Nattokinase decreases plasma levels of fibrinogen, factor VII, and factor VIII in human subjects. Nutr Res. 2009 Mar;29(3):190-6.
6. Kim JY, Lee JH, Paik JK, et al. Effects of nattokinase on blood pressure: a randomized, controlled trial. Hypertens Res. 2008;31(8):1583-8. 
7. Takabayashi T, Imoto Y, Sakashita M, et al. Nattokinase, profibrinolytic enzyme, effectively shrinks the nasal polyp tissue and decreases viscosity of mucus. Allergol Int. 2017 Oct;66(4):594-602.
8. Metkar SK, Udayakumar S, Girigoswami A, Girigoswami K. Natural serine proteases and their applications in combating amyloid formation. ADMET DMPK. 2024 Nov 16;12(6):797-820.
9. Hsu RL, Lee KT, Wang JH, Lee LY, Chen RP. Amyloid-degrading ability of nattokinase from Bacillus subtilis natto. J Agric Food Chem. 2009 Jan 28;57(2):503-8.