When you buy food supplements with probiotics, you can see “CFU” for the probiotic quantity written on the label. What does this acronym mean ? CFU for Colony Forming Unit is the unit for counting the number of live bacteria, each giving rise to a colony in the tested sample. This is the value derived from the viability analysis (microbiology test). Therefore, it gives the quantity of viable probiotics contained in the product. . LC Reference Picture: Freepik