Probiotics act as signals to the microbiome rather than typically colonizing the gut.

“That probiotics generally don't colonize the gut. that they may actually be acting as sort of a tilling process in the gut or a selectivity process because one of the things that you talk about in your book is that there are studies which show that even killed formulations of probiotics can have an effect in the gut that perhaps it's not that these organisms are they're not colonizing the gut. We're not trying to reede the gut, but we're putting in this genetic material. We're putting in organisms which kind of press the buttons on the ecosystem and shift populations like they're they're having almost like a a grooming effect.”