Top Nattokinase Benefits for Heart, Sinus & Brain Health*

Content Updated February 25, 2026

Healthy blood flow is vital to keep your heart and cardiovascular system healthy. Good circulation delivers oxygen to your cells and organs, including the heart. If your blood isn’t flowing smoothly through your veins, it can be like a traffic jam on the interstate. 

One of the best ways to support healthy blood flow is with a supplement called nattokinase—the Japanese secret to healthy longevity.* 

Here, we'll discuss the history of nattokinase; the benefits of supplementing with nattokinase and other complementary ingredients; what to look for in a quality supplement; and when to be cautious against using a nattokinase supplement. 

What is Nattokinase?

Nattokinase is a beneficial fibrinolytic enzyme produced from Natto, a traditional Japanese food made from fermented soybeans. Soaked beans are boiled, fed with a Bacillus subtilis starter, and then fermented in a warm container for about 24 hours. As the bacteria work to try to digest the soybeans, they naturally produce the enzyme known as nattokinase. 

This unique enzyme boasts one of the impressive abilities to help maintain healthy blood flow among conventional circulation-supporting supplements.^1* There are years of research to back up its use in circulatory health and other factors involved in heart health.* 

5 Science-Backed Nattokinase Benefits* 

In 1980, Hiroyuki Sumi, a Japanese researcher at the Chicago University Medical School, found that the traditional Japanese food natto can dissolve artificial fibrin.² Fibrin is an insoluble protein formed during blood clotting that creates a fibrous mesh intended to slow the blood flow.*  

Sumi and his colleagues isolated the enzyme from natto that was responsible for the breakdown of fibrin, and nattokinase was born.*  

A great deal of research on nattokinase health benefits has come out of Japan, Korea, and China. Now, Western health practices are also recognizing its ability to help maintain healthy blood flow and blood pressure levels within normal ranges.^1* 

1. Promotes Optimal Blood Flow & Circulation*  

Nattokinase is a beneficial way to support healthy blood flow.* Animal^5,6 and human studies^4,7 show that nattokinase helps to provide support to the circulatory system by keeping blood flowing smoothly.*

Nattokinase helps to keep arteries strong and limit build-up that could interfere with healthy blood flow.¹⁰* In one animal model studying suppressed blood flow in the carotid artery, nattokinase was shown to restore 62% of arterial circulation in affected animals.^1*

It's a fibrinolytic enzyme, which means it helps to break down fibrin.* It aids in maintaining healthy levels of plasminogen activator inhibitor-1 (PAI-1), a protein that interferes with the breakdown of clots.³* Low levels of PAI-1 can get in the way of wound healing, whereas levels that are too high may lead to unhealthy clotting.*

In a study of healthy young males, one dose of nattokinase was all it took to promote healthy coagulation by starting to break apart fibrin.⁷*

Nattokinase supports healthy levels of fibrinogen, another protein that supports normal blood clotting.⁴* Nattokinase is also a preferred proteolytic enzymes supplement due to its ability to break down protein without breaking down muscle tissue.*

2. Supports Healthy Blood Pressure Levels*  

By supporting the circulatory system and healthy clotting abilities, nattokinase may help to maintain both healthy systolic (the pressure exerted during the beat of the heart) and diastolic (the pressure between beats) blood pressure⁸.

Its unique way of working within the body helps to holistically support blood pressure levels within normal ranges by supporting the entire path of blood circulation to and from the heart.*

It also promotes the integrity and structure of arterial walls to support heart health.⁹*

3. Helps to Maintain Normal Cholesterol & Lipid Levels* 

Although not all studies are consistent, research shows that nattokinase may help to maintain cholesterol levels within the normal range.* Nattokinase helps to minimize the peroxidation of lipids, including oxidation of low-density lipoprotein (LDL) cholesterol.¹²* Oxidation of cholesterol in the body is a process that enhances the harmful effects of LDL or “bad cholesterol”.

In a four-month randomized, double-blind, placebo-controlled trial, nattokinase supplementation in 113 people supported healthy levels of total cholesterol, LDL cholesterol, non-high-density cholesterol (non-HDL-C), and the LDL cholesterol to HDL ratio.¹³*

4. Supports Sinus & Respiratory Health*  

While the main benefits of nattokinase center around heart health & circulation, this amazing enzyme helps to support other areas of health within the body, including comfortable respiration.*

Your lungs need healthy, strong circulation to function optimally, just like the heart.* By supporting the circulatory system, a practitioner-formulated nattokinase supplement also supports breathing, oxygen flow, and the normal breakdown of fibrin, especially during the natural aging process.*

One study shows promising results for nattokinase as support for sinus and nasal comfort.¹⁹* Nattokinase's ability to help break down fibrin helps to support healthy, comfortable nasal tissue, particularly among those with seasonal or environmental allergies.*

Because it can help to dissolve unwanted proteins, nattokinase may also play a role in immunity.¹⁵*

5: Helps to Support Neural Function & Brain Health*  

Heart health and brain health are linked: nearly 20% of the blood supply is pumped from the heart to the brain. Healthy circulation means that oxygen and other important nutrients can be delivered to the brain for optimal focus, memory, mood, and more.*

Because of its ability to promote healthy circulation, nattokinase helps to support healthy blood flow to the brain.* This in turn supports normal function of neurons and the nervous system.*

As a proteolytic enzyme, nattokinase can also help to dissolve unwanted proteins.¹⁴* Researchers are looking into nattokinase as a possible way to support healthy memory and cognition during aging.¹⁴*

Daily Nattokinase Usage: How Much Should You Take?  

While there is no official, consistent recommendation for how much nattokinase to take daily for optimal results, an average amount per serving tends to be around 100 mg or 2000 fibrinolytic units (FU) per day.

On the recommendations of our Research & Development teams and the Scientific Review Board, our Nattokinase Plus™ boasts a potent 3,000 FU of nattokinase enzyme activity, at 20,000 FU/gram.

Nattokinase Cautions & Possible Interactions  

Like with all supplements, nattokinase may not be appropriate for all users.  

Your doctor will be able to talk to you about any possible interactions between nattokinase and any other supplements, vitamins, herbs, or medications that you're currently taking. For example, nattokinase is not recommended to use alongside warfarin or blood pressure medication. It may also not be appropriate for people who are pregnant or may become pregnant or breastfeeding.

Nattokinase interactions with certain medications can be serious. It's always best to consult with your doctor or a trusted healthcare practitioner before adding any new supplement to your routine.

Nattokinase vs. Natto: Supplement vs. Food  

Natto, a staple for many Japanese foodies, has yet to find widespread popularity in the United States.

Part of that may be availability; you're not likely to find high-quality, authentic natto in your neighborhood grocery store. Its lack of popularity may also be due to its unique texture (slimy, stringy, and goopy) and its even more unique smell (funky, oceanic, and pungent).

All that to say, natto is an acquired taste on par with tripe and durian fruit.

Natto is a natural source of the enzyme nattokinase, but it only yields about 24 – 28 FU per gram and, as discussed above, may not be easy to eat for all people. Nattokinase supplements, however, remove most of the sensory experience and can offer significantly higher enzyme levels per serving.

Nattokinase Plus™ capsules are small and easy to swallow, and the recommended serving amount is only 2 capsules per day.

Slightly easier than gobbling up 125 grams of ripe, beany, smelly natto every day.

How to Choose The Best Nattokinase Supplement

When selecting a nattokinase supplement, it’s important to choose one that indicates the enzyme activity of the supplement. On the label, you should see this reported as FU/gram. If the label only reports the milligram amount, it is not enough to tell you the extent of enzymatic activity.

As mentioned above, our Nattokinase Plus™ capsules offer an impressive 20,000 FU/gram—3000 FU per serving.

The best supplements for circulatory health will likely contain synergistic ingredients to support blood flow and healthy blood vessels, rather than focusing on one single ingredient.* Nattokinase Plus™ combines nattokinase with serratiopeptidase, another beneficial enzyme, and a bioflavonoid called rutin.

Natto NSP-2™

• A clinically studied form of nattokinase
• Made from non-GMO soy
• More stable than other leading forms of nattokinase²⁰*
• Helps to keep the arteries strong and blood flowing smoothly*
• Promotes a healthy inflammatory response*
• Helps to support physical comfort¹⁶*
• May help strengthen the collagen structure of vein walls¹⁷*
• Helps to maintain levels of glutathione, the body’s master antioxidant¹⁸*
• May help support the heart against substances like phthalates¹⁷*

Serratiopeptidase

• Helps to keep the arteries strong and blood flowing smoothly*
• Promotes a healthy inflammatory response*
• Helps to support physical comfort¹⁶*

Rutin

• May help strengthen the collagen structure of vein walls¹⁷*
• Helps to maintain levels of glutathione, the body’s master antioxidant¹⁸*
• May help support the heart against substances like phthalates¹⁷*

Supporting Wellness WITH Nattokinase

If you want healthy blood vessels and a strong cardiovascular system, nattokinase can be a great supplement for many people.*

Over the last 40 years, research continues to back up its ability to help maintain a healthy circulatory system.* If you're looking for superior support for cardiovascular, metabolic, brain, and respiratory health—and you're not ready to dive into the world of slimy fermented soybeans—give Nattokinase Plus™ a try.*

References

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[3] Suzuki Y, Kondo K, Matsumoto Y, et al. Dietary supplementation of fermented soybean, natto, suppresses intimal thickening and modulates the lysis of mural thrombi after endothelial injury in rat femoral artery. Life Sci. 2003;73(10):1289-1298. 
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[6] Sumi H, Hamada H, Nakanishi K, Hiratani H. Enhancement of the fibrinolytic activity in plasma by oral administration of nattokinase. Acta Haematol. 1990;84(3):139-143. 
[7] Kurosawa Y, Nirengi S, Homma T, et al. A single-dose of oral nattokinase potentiates thrombolysis and anti-coagulation profiles. Sci Rep. 2015;5:11601. 
[8] Jensen GS, Lenninger M, Ero MP, Benson KF. Consumption of nattokinase is associated with reduced blood pressure and von Willebrand factor, a cardiovascular risk marker: results from a randomized, double-blind, placebo-controlled, multicenter North American clinical trial. Integr Blood Press Control. 2016;9:95-104. 
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[12] Iwai K, Nakaya N, Kawasaki Y, Matsue H. Antioxidative functions of natto, a kind of fermented soybeans: effect on LDL oxidation and lipid metabolism in cholesterol-fed rats. J Agric Food Chem. 2002;50(12):3597-3601. 
[13] Liu X, Zeng X, Mahe J, et al. The Effect of Nattokinase-Monascus Supplements on ... : A Four-Month Randomized, Double-Blind, Placebo-Controlled Clinical Trial. Nutrients. 2023;15(19). 
[14] Fadl NN, Ahmed HH, Booles HF, Sayed AH. Serrapeptase and nattokinase intervention for relieving ... Hum Exp Toxicol. 2013;32(7):721-735. 
[15] Tanikawa T, Kiba Y, Yu J, et al. Degradative Effect of Nattokinase on Spike Protein of ... Molecules. 2022;27(17). 
[16] Tamimi Z, Al Habashneh R, Hamad I, Al-Ghazawi M, Roqa'a AA, Kharashgeh H. Efficacy of serratiopeptidase after impacted third molar ... : a randomized controlled clinical trial. BMC Oral Health. 2021;21(1):91. 
[17] Huang R, Shi Z, Chen L, Zhang Y, Li J, An Y. Rutin alleviates ... Eur J Pharmacol. 2017;814:151-160. 
[18] Rahmani S, Naraki K, Roohbakhsh A, Hayes AW, Karimi G. The protective effects of rutin on the liver, kidneys, and heart by counteracting organ toxicity caused by synthetic and natural compounds. Food Sci Nutr. 2023;11(1):39-56. 
[19] Takabayashi T, Imoto Y, Sakashita M, Kato Y, Tokunaga T, Yoshida K, Narita N, Ishizuka T, Fujieda S. Nattokinase, profibrinolytic enzyme, effectively shrinks the nasal polyp tissue and decreases viscosity of mucus. Allergol Int. 2017 Oct;66(4):594-602. doi: 10.1016/j.alit.2017.03.007. Epub 2017 Apr 4. PMID: 28389065. 
[20] Natto NSP-2™. Retrieved February 2026 from https://nattonsp2.com/