What Is Nattokinase? Benefits, Differences from Natto Bacteria, and How to Take It Safely

“I heard on TV that nattokinase is good for circulation—but how should I take it?”

Nattokinase is a naturally occurring enzyme found in natto, a traditional Japanese fermented soybean food. It is produced during the fermentation process by Bacillus subtilis natto and is known for its ability to break down proteins. Because of this characteristic, nattokinase has been widely studied in relation to blood flow and circulatory health, and it has gained attention among people who are mindful of their daily lifestyle and diet.

Unlike natto bacteria themselves, nattokinase is an enzyme rather than a living microorganism. It is sensitive to heat and stomach acid, which means its effectiveness can vary depending on how it is consumed. In this article, we’ll clearly explain what nattokinase is, how it differs from natto bacteria, what research suggests about its functions, and how to incorporate it safely and realistically into everyday life.

Is Nattokinase the Same as Natto Bacteria?

Nattokinase is an enzyme produced during the fermentation of natto. Its primary role is breaking down proteins.

Importantly, natto is the only food that naturally contains nattokinase. While nattokinase is now also available in supplement form, it is sensitive to heat and acidic conditions, meaning that cooking methods or stomach acid may reduce its activity. Because of this, how it is consumed matters.

Natto bacteria, on the other hand, are the microorganisms responsible for fermenting soybeans into natto. These bacteria are relatively resistant to heat and stomach acid and are known to reach the intestines alive.

In short:

• Nattokinase = an enzyme created by natto bacteria during fermentation
• Natto bacteria = microorganisms that drive the fermentation process

Though closely related, they play very different roles.

What Does Nattokinase Do in the Body?

Nattokinase has been studied in connection with various wellness topics. Below are some areas where it has drawn research interest.

Supporting Healthy Blood Flow

Nattokinase is a protein-degrading enzyme, and research has focused on its interaction with fibrin, a protein involved in blood clot formation. Because of this, nattokinase is often discussed in relation to circulation.

It’s important to note that these findings are based on ongoing research, and individual responses vary. Rather than viewing nattokinase as a remedy, it’s best approached as part of a balanced diet that includes natto as a traditional food.

Blood Pressure–Related Research

Foods containing nattokinase have been studied in populations with slightly elevated blood pressure, examining their relationship with blood flow and internal balance.

In Japan, some nattokinase-containing products are registered as Foods with Function Claims, meaning manufacturers submit scientific evidence and usage guidelines to the government. These labels provide information such as recommended intake and precautions, helping consumers make informed choices.

Daily Wellness Support

Because nattokinase is a naturally occurring component of natto, it can be relatively easy to incorporate into daily meals. Research continues to explore how nattokinase interacts with the body’s internal environment, making it of interest to those aiming to maintain everyday wellness through diet.

Interest from Beauty-Conscious Consumers

Healthy circulation plays a role in delivering oxygen and nutrients throughout the body, which is why nattokinase is sometimes mentioned in discussions around beauty and vitality. While not a cosmetic ingredient, it is often introduced as part of a diet that supports overall balance.

Oral Health Research

Nattokinase has also appeared in studies related to biofilms, the sticky bacterial layers that form on teeth and are associated with cavities and gum disease. Some research has observed changes in biofilm structure when nattokinase is introduced under specific conditions.

How Can You Get Nattokinase Naturally?

There are two main ways to consume nattokinase: through natto or via supplements.

Getting Nattokinase from Natto

Eating natto is the most natural way to consume nattokinase. A commonly referenced serving is one standard pack per day (about 40–50 g).

Nattokinase activity is measured in FU (Fibrin Units), which indicates how effectively the enzyme breaks down fibrin. Higher numbers reflect stronger enzymatic activity.

As a reference:

• One pack of natto (about 50 g) may contain around 1,500 FU
• The Japan Nattokinase Association suggests 2,000 FU per day as a general reference value

Actual amounts vary by product, manufacturer, and freshness. Consuming natto as part of a regular meal—without overdoing it—is usually the most practical approach. Excessive intake may cause digestive discomfort in some people.

Taking Nattokinase Supplements

Supplements are an option for those who want a more controlled intake.

Because nattokinase is sensitive to heat, cooked natto dishes may reduce its activity. Supplements avoid this issue. Some products also use acid-resistant capsules to help protect the enzyme from stomach acid.

Natto naturally contains vitamin K, which plays a role in blood clotting. Some nattokinase supplements remove vitamin K during manufacturing, making them easier to consider for individuals who need to monitor vitamin K intake. Always check labels carefully.

When Should You Take Nattokinase?

Nattokinase can be taken at a time that fits your lifestyle. Some people prefer evening intake or before bedtime, as circulation tends to slow during rest. Others take it with dinner as part of a regular routine.

If you have a sensitive stomach, taking nattokinase after meals may feel gentler. The most important factor is consistency and choosing a time you can comfortably maintain.

Are There Any Risks or Precautions with Nattokinase?

People Taking Warfarin or Similar Medications

Those using anticoagulant medications such as warfarin should be cautious. Vitamin K, found in natto and some supplements, can interfere with these medications. Always consult a healthcare professional before consuming natto or nattokinase supplements.

During Pregnancy or Breastfeeding

Supplement labels often advise caution for pregnant or breastfeeding individuals. If considering supplements, consult a doctor or pharmacist. Natto as a regular food may be consumed in moderation as part of a normal diet.

Incorporating Nattokinase into a Healthy Lifestyle

Nattokinase has been studied in relation to circulation, blood pressure, and oral health, making it a component of interest for people focused on lifestyle balance and wellness.

Whether through traditional foods or supplements, it can be incorporated in a way that fits your daily routine, without excess or strain.

An Easy Way to Make Natto Part of Your Routine

If eating natto every day feels challenging, capsule-based natto products can be an alternative. Products like sonomono Natto allow you to benefit from spore-forming natto bacteria, which are known for surviving digestion, while maintaining a simple daily habit.