Peter Attia

I would say those are the two main reasons why it has been not easy to come up with, I think, some more concrete points of view on this particular nutrient.

I think this is actually a very important point.

And this is an AMA where I found myself learning a lot in the preparation for it with the research team.

So in nutrition, dietary fiber refers to a diverse group of compounds that make their way to the large intestine.

So why is that relevant?

Well, if you think about how your digestion works, put things in your mouth, digestion actually begins in the mouth.

You've got these enzymes in the mouth that are already starting to break things down, but mostly the mouth is for mechanical breakdown.

The stomach then undergoes more of a breakdown, right?

So now you've got this high acid environment and other enzymes in the stomach that break things down further.

The stomach then exits the food stuff into the proximal part of the small intestine called the duodenum and then ultimately ilium jejunum.

And that's where the bulk of nutritional absorption takes place.

But of course, this is what separates fiber from many of the other things we consume, which is the enzymes can't break down fiber.

So they actually make their way all the way to the large intestine.

Now, these compounds that make their way to the large intestine are virtually always carbohydrate-based.

And that's why if you look at a nutrition label, you'll usually see fiber as kind of a subset of carbohydrates.

But it usually doesn't count towards the caloric content because you're not really using them for energy.

The common thread across fiber types is that we can't digest them.

But that's really where the similarities end and where the chemical composition of fibers vary widely.

This is where you start to get into...

at least for me, kind of a nomenclature and a set of explanations that actually is quite complicated and probably worth getting into a bit more.