The Colon Journal
A short course on the organ nobody taught you about.
Twenty-one chapters, in order, from where your food goes to why the last metre of your colon decides so much. No prior biology needed.
Fibre helps constipation.
The colon is an organ I never understood. Fibre is how I feed it.
Part 1
Meet your gut
Where food goes, what gets absorbed, and the one thing your body cannot break down.
By the end you will know which organ does what — and which one fibre is really for.
02 What actually gets absorbed?A short inventory of what your small intestine takes out, so you can see what it leaves behind.
03 Why humans cannot digest fibreThe reason is a bond your enzymes cannot read — and it is where the word prebiotic finally earns a...
Part 2
The forgotten organ
Why the colon is a fermentation chamber rather than a waste bin, and who lives in it.
Four jobs, only one of which is disposal — and why the slowest organ in your gut is slow on...
05 Meet your second digestive systemNot good bacteria and bad bacteria, but a workshop of specialists where one worker's output is the next one's raw...
06 What is fermentation, actually?Energy without oxygen, why gas is a by-product rather than a fault, and the one variable that decides comfort.
Part 3
What fermentation makes
Prebiotic, probiotic, postbiotic — and the short-chain fatty acids the rest of your body notices.
Three words used interchangeably that sit at three different points on the same pathway.
08 The three short-chain fatty acidsAcetate, propionate and butyrate are not variations on one theme. Where each one goes decides what it can do.
09 Butyrate: fuel for the colonYour colon lining runs on a molecule your microbes make — and burning it maintains the conditions for making more.
10 Your colon is not one placeFermentation front-loads at the caecum and thins towards the sigmoid. Why the far end is the interesting end — and...
11 When the fuel runs outBacteria that run out of fibre switch to protein. What that produces, where it happens, and what carbohydrate fermentation suppresses...
Part 4
Why diversity matters
No single fibre does every job. What follows from that, and what a designed spectrum looks like.
These chapters are in draft. We publish them once the science has been checked, not to fill a page.
soonPart 5
The colon in daily life
Regularity, appetite, glucose, cholesterol, the gut lining — mechanism first, then honestly where the evidence stops.
These chapters are in draft. We publish them once the science has been checked, not to fill a page.
soonReference library
Shorter answers
Standalone pieces that answer one question directly. Not part of the reading order.