These three types of Red Yeast Rice have similar appearance, but are different in the microbial strain and the technical process. Only the Red Yeast Rice which contains Monacolin K is called functional Red Yeast Rice. The production of functional Red Yeast Rice is a process of growing natural active ingredients from Monascus Purpureus by the secondary metabolism through fermentation. This process yields natural active Monacolin K which helps lower levels of cholesterol in blood. Therefore the Monacolin K content is the key specification of function Red Yeast Rice.