Hello I,

FOS is a natural source of dietary fiber known as a prebiotic, and prebiotics have been shown in several studies to help promote the growth of beneficial bacteria (known as probiotics) in the gut. As such, we add FOS to our probiotic supplements to provide a food source for the healthy probiotics and stimulate their growth, thus improving overall digestive and immune health. The FOS in Ultimate Flora Critical Care 50 Billion is sourced from chicory and is not the type of FOS shown to cause digestive irritation/discomfort.

With regard to culture count, there are indeed 50 billion active cultures in Ultimate Flora Critical Care 50 Billion when it reaches consumers. In order to guarantee this count, the product starts out with roughly double that amount so that we are able to ensure with certainty that it contains at least 50 billion active cultures through the product expiration date (under recommended storage conditions)--as stated in our Potent-GUARD guarantee.