Fibre
The parts of plants your own enzymes can’t cut. Some of it feeds the crew; some just keeps things moving.
What it is
Fibre is the part of plant food your own enzymes can’t digest. It’s a big family: cellulose in plant walls, pectin in fruit, beta-glucans in oats, inulin and FOS, resistant starch in cooled potatoes and green bananas.
Some fibre dissolves in water and gets fermented by the crew (soluble). Some doesn’t, and mostly passes through, adding bulk and keeping things moving (insoluble). Most plant foods carry a mix.
AnnouncerCows have four stomach compartments and still need microbes for cellulose. You have one stomach. Bring friends.
Fibre is the part of plants your own enzymes can’t cut. The crew can, which is why it ends up feeding them.
Cooked-then-cooled potatoes and rice carry more resistant starch than hot ones: some of the starch re-packs into a shape amylase can’t get into.
Try your tools on it
Your enzymes fit a short list of links: the ones in starch, table sugar, milk sugar and protein. Plants use plenty of other links, and you have no tool for those. Cellulose, for example, is all glucose, joined a way amylase can’t touch.
A plate of fibre
glucose fructose
Who eats it, Downtown
Hundreds of kinds of colon microbes, each with its own favourite fibres. Fermentable fibre feeds them; insoluble fibre mostly rides through.
Biff
Lacey
ShortyWhat they make
From the fermentable kinds: acetate, propionate and butyrate, roughly three acetates for every propionate and every butyrate. Plus gas. Butyrate is the main fuel for the cells lining your colon.
Serve the fibre to the crew and see what they make.
Where you’ll find it
Beans and lentils- Oats
Whole grains
Fruit- Vegetables
- Nuts and seeds
Where it ends up: Downtown, on the map.
Coming up next on Channel GG
The Glossary
Gut words from A to Z, true and silly side by side.
