Nattokinase is a fibrinolytic enzyme identified and isolated in 1987 from a specific Japanese food called natto (a kind of vegetable cheese). Since its discovery and until now, nattokinase has been studied experimentally and clinically almost exclusively in Japan, China, Korea and other countries in the respective geographical area, resulting in a complex picture of potentially useful properties in clinical practice. Nattokinase was approved for use in Europe in 2016 by EFSA (European Food Safety Authority) as a food supplement.