From Sloan Kettering: · Nattokinase is an extracelluar enzyme secreted by the bacterium Bacillus subtilis, used to ferment boiled or steamed soybeans resulting in a preparation called nattō. Nattō has been consumed as food in Japan for several centuries. Nattokinase is also available as a supplement and is most known for its effects on prevention and treatment of clots and to improve blood circulation.

From WebMD: https://www.webmd.com/vitamins/ai/ingredientmono-1084/nattokinase
Please note that any supplement or substance that operates to thin blood should be discussed with your provider before use, especially if you take ANY medications or have any heart, blood or circulatory issues.
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