Your microbiome takes time to adapt to what you're eating and if you drastically increased fiber suddenly, it was likely not prepared for it. It could also have

Your microbiome takes time to adapt to what you're eating and if you drastically increased fiber suddenly, it was likely not prepared for it. It could also have had a weak ability to deal with certain types of fiber. Often it's oligosaccharides (beans). The FODMAP process helps you figure out which fiber your gut may be sensitive to and then you can start low and gradually increase it over time.