When it comes to natural remedies for cardiovascular health, one enzyme has been gaining significant attention in recent years—nattokinase. Derived from a traditional Japanese food called natto, this enzyme has powerful properties that support healthy circulation, reduce clot risk, and promote overall heart and vascular health.
For centuries, natto has been a staple in Japan, valued not only for its distinct flavor but also for its remarkable health benefits. Today, nattokinase is widely available as a supplement, often promoted for blood flow, heart protection, and longevity. But what exactly is nattokinase? How does it work? And what does science say about its benefits?
This article breaks down everything you need to know about nattokinase—its origins, mechanisms, health benefits, safety, and how to incorporate it into your wellness routine.
What Is Nattokinase?
Nattokinase is a serine protease enzyme extracted from natto, a traditional Japanese dish made by fermenting soybeans with a specific bacterium called Bacillus subtilis natto. Natto has been consumed in Japan for over 1,000 years and is associated with lower rates of cardiovascular disease among regular consumers.
In the 1980s, Japanese researcher Dr. Hiroyuki Sumi discovered that natto contained a unique enzyme capable of dissolving blood clots. He named it nattokinase, and subsequent research has shown that it may improve circulation and support vascular health in multiple ways.
How Nattokinase Works
The cardiovascular benefits of nattokinase stem from its ability to influence blood clotting, fibrinolysis (the breakdown of fibrin), and circulation.
Fibrinolytic Activity
Nattokinase helps break down fibrin, a protein involved in blood clot formation. Excess fibrin can contribute to poor circulation, clotting disorders, and cardiovascular disease.
By enhancing fibrin breakdown, nattokinase promotes smoother blood flow.
Blood-Thinning Effects
Nattokinase appears to reduce blood viscosity (thickness) and may help prevent abnormal clot formation.
Unlike pharmaceutical blood thinners, nattokinase works more gently, though it can still significantly influence clotting activity.
Blood Pressure Regulation
Some studies suggest that nattokinase helps lower blood pressure by breaking down fibrinogen and improving arterial flexibility.
It may also increase nitric oxide levels, which relaxes and widens blood vessels.
Together, these mechanisms explain why nattokinase is often promoted as a natural circulation enhancer and cardiovascular support.
8 Science-Backed Health Benefits of Nattokinase
1. Supports Healthy Circulation
Nattokinase improves overall blood flow by breaking down fibrin and reducing blood viscosity. This effect helps ensure oxygen and nutrients reach tissues efficiently, supporting heart health, brain function, and physical endurance.
2. Helps Prevent Abnormal Clot Formation
Clots (thrombosis) can block blood vessels, leading to serious events such as stroke, heart attack, or deep vein thrombosis (DVT). Research suggests that nattokinase helps reduce the risk of abnormal clotting by enhancing natural fibrinolytic activity.
In laboratory and animal studies, nattokinase has been shown to dissolve existing clots and reduce fibrin accumulation. Early human studies support its potential role as a preventive measure for thrombotic conditions.
3. Blood Pressure Management
Several clinical studies indicate that nattokinase supplementation may lower blood pressure in individuals with hypertension. One study found that daily supplementation with nattokinase reduced systolic blood pressure by an average of 5–10 mmHg after 8 weeks.
This benefit likely comes from its ability to improve vascular flexibility and reduce blood vessel stiffness.
4. Stroke and Brain Health Protection
Because nattokinase improves circulation and reduces clot risk, it may offer neuroprotective benefits. Poor blood flow and clot formation are key risk factors for ischemic stroke. By keeping vessels clear and flexible, nattokinase may help lower stroke risk and support brain health as we age.
5. Heart Health Support
Nattokinase supports the cardiovascular system in multiple ways:
Reducing clot risk.
Lowering blood pressure.
Improving circulation and arterial flexibility.
Together, these benefits contribute to overall heart health and may reduce the likelihood of cardiovascular events.
6. Anti-Inflammatory Effects
Emerging research suggests that nattokinase may reduce inflammation in blood vessels. Chronic vascular inflammation contributes to atherosclerosis (plaque buildup in arteries). By lowering inflammation, nattokinase could help keep arteries clearer and healthier.
7. Enhanced Longevity and Vitality
Natto, the food source of nattokinase, has been consumed for centuries in Japan and is associated with longer lifespans and reduced cardiovascular disease rates. While nattokinase supplements isolate one compound from natto, they carry some of the same benefits, potentially supporting healthy aging and vitality.
8. Support for Vein Health
Poor circulation can contribute to conditions like varicose veins and chronic venous insufficiency. By thinning the blood and improving flow, nattokinase may relieve swelling, heaviness, and discomfort associated with venous problems.
Food vs. Supplement: How to Get Nattokinase
Natto (Food Source):
Eating natto provides nattokinase naturally, along with other nutrients like vitamin K2, protein, and probiotics. However, natto has a strong flavor and sticky texture that many people find unappealing.Nattokinase Supplements:
Supplements provide standardized amounts of nattokinase without the taste of natto. They are typically measured in fibrinolytic units (FU), which reflect enzymatic activity.
Typical Dose: 2,000 FU to 4,000 FU per day, usually taken on an empty stomach for best absorption.
Safety and Side Effects
Nattokinase is generally considered safe for most healthy adults. However, because it affects clotting, it should be used cautiously in certain populations.
Potential Side Effects:
Increased risk of bleeding or bruising.
Gastrointestinal upset in some users.
Precautions:
Not recommended for people taking blood-thinning medications (such as warfarin, aspirin, or clopidogrel) without medical supervision.
Not advised for people with bleeding disorders or scheduled surgery.
Pregnant or breastfeeding women should avoid supplementation unless directed by a healthcare professional.
Who Can Benefit from Nattokinase?
You may benefit most from nattokinase if you:
Have high blood pressure.
Want natural support for circulation and cardiovascular health.
Are at risk of clot-related issues (with medical approval).
Experience poor circulation, varicose veins, or swelling in the legs.
Are seeking natural strategies for heart and vascular wellness.
Nattokinase vs. Other Circulation Supplements
Fish Oil (Omega-3s): Supports circulation by reducing inflammation and triglycerides, but does not directly break down fibrin.
CoQ10: Supports mitochondrial energy and heart muscle strength, but does not directly affect clotting.
Nattokinase: Unique in its ability to target fibrin and enhance natural clot-dissolving pathways.
Each plays a different role, and they can often be used together for a comprehensive cardiovascular strategy (with medical guidance).
Final Thoughts
Nattokinase is a fascinating natural enzyme with powerful potential to support circulation and cardiovascular health. By enhancing the body’s natural ability to dissolve fibrin, it improves blood flow, reduces clot risk, and may help regulate blood pressure.
While more large-scale human studies are needed to fully establish its benefits, current evidence suggests nattokinase is a promising tool for those looking to protect their heart and vascular system naturally.
If you’re considering nattokinase supplementation, talk to your healthcare provider first—especially if you’re on blood thinners or have underlying health conditions. But for many health enthusiasts, nattokinase offers a safe, natural way to keep the blood flowing smoothly and the heart beating strong.