An enzyme (a kind of protein) that supports the health of the heart and blood is nattokinase. According to studies, nattokinase dissolves blood clots, improving blood flow, preserving the structural integrity of blood arteries, and reducing the risk of heart disease. It is obtainable from "Natto," a well-known Japanese delicacy prepared from fermented soybeans. However, you can still get the nattokinase benfits by taking supplements if you can't locate Natto or any other food containing the enzyme.