Nattokinase™ capsules from Good Health Naturally contain nattokinase and another powerful antithrombotic substance, rutin. Rutin is a bioflavonoid that helps strengthen and increase flexibility in blood vessels. Research shows that nattokinase has fibrinolytic activity, which supports the body in breaking up and dissolving unhealthy blood coagulation. Because it so closely resembles plasmin, it dissolves fibrin directly. This leads to smoother blood circulation and has had over 50 studies and papers published on PubMed over the past 30 years.