how does fiber work to help both constipation AND diarrhea? how can it do both of those things?

Question

I’ve heard people say, “if you’re constipated, you need more fiber in your diet.” and I’ve also heard people say, “if you’re having diarrhea, you need more fiber in your diet.” does fiber really help with both? and if so, how? I would think that fiber would help with diarrhea but make constipation worse. (TMI) >!but multiple times, eating fiber-heavy foods like flax seeds has caused diarrhea for me.!<

TLDR: how does fiber work to influence your bowel movements??

In: Biology

Answer 1

It also depends on the type of fiber. There’s soluble, and insoluble. Soluble fiber is fiber we can digest, and functions to “lube” your GI tract. Insoluble is fiber we can’t fully digest (think about when you see corn bits in your stool), and functions to bind your stool together.
If you’re constipated, more soluble fiber will help (in addition to more water). If you have diarrhea, more insoluble fiber will help.