Low baseline microbial diversity may lead to adverse inflammatory reactions to high fiber intake.

“And the key factor that came out was the baseline microbial diversity. And so the idea here was that people who had low diversity, like a compromised western diet, depleted diversity, when they stuffed all that fiber down their gullet, they actually had an adverse reaction to it.”

“those with the highest microbial diversity at baseline tended to be the people who had a more beneficial immune response to fiber”