The research pointed out that even in the same village, on the same diet, in the same genetic family or different families, there were differing probiotic strains dominant in peoples' gut. Probiotics given changed the dominant strains, but the original probiotic strains reasserted themselves when the canned probiotic dose was withdrawn. That is even within the same types of bacteria (bifidobacteria and lactobacilli) but differing subtypes.
Further, when the probiotic is withdrawn, even a bad conmdition will reassert itself if you aren't feeding your probiotics on inulin.
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