Colony Forming Units (CFU) is a marketing metric for probiotics representing the number of colonies that grow on a petri dish.

“some brilliant marketer decided that that was going to become the metric the name of the game for probiotics um so Colony forming units again little remember back to seventh grade biology where you might have been given a petri dish and you had to like swab your mouth or swab your hand or put your finger on it and then you see what grows that's that's basically that that tool so you take your um you know your pill or or whatever ever your yogurt and you you basically spread it out on a petri dish and then you count how many colonies form and that gives you a number so you'll say well gee this pill has you know 10 to the 9th Colony forming units in it so you know some marketer decided that that's the most important thing is the number of colony forming units but it's less relevant than than the function of what's happening in your pill”

“so Colony forming units again little remember back to seventh grade biology where you might have been given a petri dish and you had to like swab your mouth or swab your hand or put your finger on it and then you see what grows that's that's basically that that tool so you take your um you know your pill or or whatever your yogurt and you you basically spread it out on a petri dish and then you count how many colonies form and that gives you a number so you'll say well gee this pill has you know 10 to the 9th Colony forming units in it”