Nattokinase is an enzyme that naturally exists in Natto, which is a fermented Japanese health food derived from soy. Most of the supplement reviews on the internet are very positive for it because it helps support critical functions like circulation and overall cardiovascular health. What it does is help promote the natural break down down of Fibrin, which is the protein involved in blood clotting, so it helps to promote healthy circulation throughout the blood stream.

There are other options on the market that are available for those who are allergic to or sensitive to soy, such as the Nattozimes that is derived from a healthy fungus called Aspergillus Oryzae... both have the same overall activity (around 2,000 "Fibrinolytic Units"). Both also have the same warnings and concerns that you should talk with your healthcare provider about before using it if you have a blood coagulation disorder or if you are taking any drugs that affect blood coagulation.