The answer is: Natto-zymes stock #: 520-7 Natto-zymes is a combination of different enzymes. When taken on an empty stomach these enzymes go into the bloodstream to clean house. They break down fibrin, which is a protein in the blood that is responsilbe for clogging and thickening the blood. In the process, Natto-zymes may also clean the arteries. This is a great product to help you prevent a heart-attack. For some people, Natt-zymes has helped lower blood pressure as well, because the blood will flow through the arteries with much more ease when it does not have all that debris in it.