Undigestible Foods: What Your Gut Can't Break Down

Dietary fibers:

- Cellulose

- Hemicellulose

- Lignin

- Pectin

- Resistant starches

Other plant components:

- Tannins

- Phytic acid

- Saponins

- Waxes

- Cutins

Animal-derived compounds:

- Chitin

- Keratin

- Collagen