Most probiotics don’t make it past your stomach. It is not how many organisms are in the capsule 5 billion, 50 billion, etc. It is how many actually survive the stomach acid in your stomach. 50 billion can become 5 billion.
New spore-based probiotics solve this issue by being inert and immune to stomach acid. Core Biotic is a spore-based probiotic that activates when it has safely passed through your stomach into your bowel.