Zia, These live cultures live in your digestive tract and are good for you. You need them to balance out the "bad" bacteria. Forgive me if I'm getting too graphic and "female" here, but when taking an antibiotic, it wipes out all bacteria, good and bad, which is why you can get a yeast infection when taking antibiotics. That's why yogurt or acidophilus pills are recommended when taking an anitbiotic. Here's more info Acidophilus lest I gross out anyone with further details.