Nattokinase: Health Benefit, Sources, Doses, and Side Effects

Most of my markers for heart disease risk looked excellent, including my triglycerides, c-Reactive Protein, blood pressure, and Hemoglobin A1c.

However, my Apo B, PLAC, oxidized LDL, and Lp(a) told a different story. Even though my diet and lifestyle support my heart health, my genetics do not. So, my doctor had me start taking nattokinase, bergamot, and a specific mix of vitamin E.

I had heard of nattokinase but wasn’t very familiar with it. So, for my own benefit, as well as yours, I delved into the research.

I wanted to understand better where nattokinase comes from, its health benefits, and how to use NK. The following is what I discovered.

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What is nattokinase?

Nattokinase (NK) comes from a popular cheese-like Asian food made by fermenting soybeans with Bacillus subtilis. Asians have eaten natto for more than 2000 years. 

Researchers observed that those who eat natto regularly have lower rates of cardiovascular disease. The correlation led them to identify the active compound, a fibrinolytic enzyme called nattokinase, in 1987. The first clinical trial was conducted in 1990.

Nattokinase is a nutritional supplement. It’s not a patentable pharmaceutical drug. Without a patent, it’s almost impossible to make enough money on it to justify multiple, expensive, double-blind, placebo-controlled studies. As a result, there aren’t as many clinical studies as there would be with a drug.

But the studies that have been done show nattokinase can play a crucial role in cardiovascular and cognitive health.

With cardiovascular disease being the number one cause of death in the western world (no, it’s not COVID-19), and growing concerns about aging people’s cognitive health, nattokinase shows promise as a natural, safe, and effective solution for supporting heart and brain health. 

Nattokinase is also unique because it affects multiple aspects of vascular health.

Health Benefits of Nattokinase

Unlike many drug therapies for cardiovascular health, nattokinase does not cause significant side effects. It has a strong safety record and is not toxic, even at high doses.

Protects against excessive blood clotting

Fibrin is a blood protein that causes coagulation. If you cut yourself, the clotting keeps you from losing too much blood. That’s a good thing under those circumstances. But when you get a blood clot inside your blood vessels, it can lead to big problems. 

Over time, clotting causes plaque formation. If a clot is large enough, and it breaks loose from your vessel walls, the clot can lead to a heart attack or stroke. 

Based on animal studies, “NK was found to be a potent antithrombotic agent, and, by reducing thrombus formation, was able to slow the progression of plaque formation.”

According to one human study, a single 100mg dose breaks down fibrin and thins the blood within four hours of consumption, reducing the risk of a clot.

In a two-month study, those taking NK experienced lower fibrinogen levels, factor VII, and factor III, which all suggest better cardiovascular health.

Doctors also recommend the daily use of low-dose aspirin as an anticoagulant, but long-term use comes with significant gastrointestinal (GI) side effects and excessive bleeding.

Nattokinase improves blood flow by supporting better blood viscosity and might be a safer alternative than pharmaceuticals that do the same thing.

Slows the progression of atherosclerosis and supports healthy blood cholesterol levels

Atherosclerosis is the ultimate cause of stroke and heart disease.

Though cholesterol is essential for your health, the oxidation of excessive cholesterol contributes to atherosclerosis. Research shows nattokinase slows the progression of atherosclerosis and supports healthy blood cholesterol levels.

As an antioxidant, it appears to reduce the oxidation of low-density lipoprotein (LDL).

Human research also shows nattokinase impacts carotid plaque size, even better than taking simvastatin.

Our data suggested that NK was a better alternative to statins, a commonly used drug to reduce atherosclerosis, and furthermore, NK could be a viable alternative therapy for cardiovascular attack and stroke in patients.

Nattokinase: A Promising Alternative in Prevention and Treatment of Cardiovascular Diseases

High doses of nattokinase support healthier blood cholesterol and triglyceride levels, though lower doses either don’t have a significant effect, or require long-term use to affect lipid levels.

Supports healthy blood pressure

Nattokinase has been shown to suppress the angiotensin-converting enzyme (ACE), which helps control elevated blood pressure. High blood pressure causes damage to blood vessels. The vascular damage leads to atherosclerosis development.

Two different 8-week studies with hypertensive people showed nattokinase supports healthy blood pressure levels. Animal research adds further support for its effects on blood pressure. However, the exact mechanism for its blood pressure effects remains unknown.


Nattokinase could play an important role in maintaining cognitive function with aging.

Though brain-related, human-based studies are challenging to conduct, numerous animal studies show NK offers cognitive benefits.

Amyloid fibrils contribute to cognitive problems like Alzheimer’s disease. Studies show nattokinase degrades amyloid fibrils. 

In addition, a strong correlation between cardiovascular disease and cognitive dysfunction exists, so NK’s impact on the cardiovascular system may impact mental health as well.

Side Effects, Drug Interactions, and Doses

With NK’s anticoagulant and blood thinning effects, patients taking aspirin, warfarin, or related drugs should only consider nattokinase with a doctor’s supervision. In addition, those who take blood pressure medication or have low blood pressure should exercise caution, since NK also impacts blood pressure.

Other than that, NK appears to be safe and very well-tolerated.

The most common nattokinase dose is 100 mg per day, which is also measured as 2000 FU, though people have tolerated doses of 150 mg (3000 FU) without issue. There may some benefit to splitting the dose throughout the day, but the most important thing is being consistent with taking it.

Read also: Hydroxytyrosol Health Benefits.


Nattokinase holds tremendous promise, especially as a cardiovascular-supporting natural supplement.

Some integrative doctors recommend nattokinase to support patients with chest pain, deep vein thrombosis (DVT), varicose veins, hemorrhoids, poor circulation, and peripheral artery disease. They may also recommend it for conditions such as fibromyalgia, chronic fatigue, fibroids, and muscle spasms. As these are all medical conditions, always check with your doctor before introducing such a supplement. Much more research is needed to see how effective NK is for these health issues as well.

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