Nattokinase Supplement

Nattokinase fermented soybeans

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Nattokinase is an enzyme extracted from natto, a Japanese food made from fermented soybeans. To make natto, boiled soybeans are combined with the bacteria Bacillus subtilis natto.

Natto is a popular breakfast food in Japan, where it is eaten with rice. Natto has a strong, cheese-like smell; a nutty, salty flavor; and a sticky consistency.

The supplement nattokinase is purified from natto and made into tablets and capsules, so it doesn't have the same strong smell or taste of the food. It's available in health food stores and online.

Uses for Nattokinase

In alternative medicine, nattokinase is purported to dissolve abnormal blood clots. Abnormal blood clotting is linked to heart attacks, stroke, and other conditions. 

So far, there is a lack of scientific support for the claim that nattokinase can dissolve blood clots. 


Nattokinase shouldn't be used by people with bleeding disorders, or by people who are taking Coumadin (warfarin), aspirin, or any other drug that influences blood clotting (unless under doctor's supervision). Nattokinase may lower blood pressure.

The safety of nattokinase supplements in healthy people isn't known. Use of the supplements could theoretically lead to easy bruising and excessive bleeding.

Natto and many nattokinase supplements contain vitamin K. Large amounts of vitamin K may interact with prescription drugs.

The safety of nattokinase in pregnant or nursing women or children is unknown.

Supplements haven't been tested for safety and due to the fact that dietary supplements are largely unregulated, the content of some products may differ from what is specified on the product label. Also keep in mind that the safety of supplements in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications has not been established.

Using Nattokinase for Health

Due to a lack of research supporting the use of nattokinase for any health condition, it's too soon to recommend it. If you're considering using it, it is essential that you talk with your primary care provider first. Self-treating a condition and avoiding or delaying standard care may have serious consequences.

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Article Sources

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  • Sumi H, Hamada H, Nakanishi K, Hiratani H. Enhancement of the Fibrinolytic Activity in Plasma by Oral Administration of Nattokinase.  Acta Haematol. 84.3 (1990): 139-143.