For me, the topic of fibre is typical of the whole area of gut health. It seems straightforward at first but soon becomes complicated and confusing.
‘Eat more fibre!’ is one of the things you hear most often about digestive health. So often in fact that we might just tune it out… ‘yeah yeah, eat more fruit and veg, blah blah, whatever!’
Fibre is crucially important to the long term health of our microbiome and therefore our entire body, but did you know that if our gut is already in a bad state, eating high-fibre foods can actually make us worse?
What is fibre?
There are different kinds of fibre and varying definitions of what it is, but the bottom line is this:
‘Fibre’ is stuff we eat that we can’t actually digest.
This begs the question: why are supposed to eat food that we can’t actually digest?!
Back in our hunter-gatherer days, fibrous material came with the plants we found and consumed. It was part of the package.
These days fibre is added to packages of breakfast cereals and snack bars by manufacturers who want you to think their food is healthy (it isn’t!).
Our cavemen ancestors couldn’t avoid fibre even if they wanted to. There was no white bread or white rice around!
Another thing our early ancestors couldn’t avoid was bacteria (and neither can we). Their guts were full of microbes, as are the guts of all living creatures. And one thing bacteria are good at, is breaking stuff down and converting it into fuel. That’s how they survive in the most hostile conditions on earth, such as volcanic undersea vents.
The result was a deal between our cavemen ancestors and their bacteria: the humans would provide food and shelter to the bacteria, and the bacteria would in turn help to break down food that we would otherwise be unable to digest, providing nutrients for them AND FOR US.
This ‘deal’ of course was never hammered out over a negotiating table but we now know this is how Mother Nature works, through symbiosis and cooperation between different species.
The result is that we are able to unlock nutritional goodness from otherwise indigestible fibre.
But it turns there are a lot more benefits to taking care of our little microscopic buddies. Read on!
Fibre Nurtures a Rich Microbiome
‘Microbiome’ is the collective name for the squillions of bacteria that live inside us. The list of ways we now know they help us is long, and getting longer every day as scientists carry out more studies.
For example, friendly bacteria help to:
- fight off ‘bad’ bacteria that would make us sick
- regulate our immune system so we’re not overwhelmed by allergies and unwanted inflammation
- regulate our metabolism and hormones so we don’t get fat
- regulate our brain development and mental state, for example by making neurotransmitters like serotonin.
When we eat fibre it feeds and supports the ecosystem that is our microbiome. For this reason foods and supplements that contain fibre are know as PREBIOTIC.
(By the way, prebiotics are not to be confused with PROBIOTICS, which are foods or supplements containing friendly bacteria.)
Without enough fibre there isn’t enough food for our many species of friendly gut bugs and they die back. This is a problem as we need as much diversity as possible in this ecosystem.
It’s exactly the same with other complex ecosystems such as rainforests and coral reefs: when they lose diversity they become weak and vulnerable to invaders or collapse.
If we regularly eat fibre our microbiome is happier. And when our microbiome is happy we immediately notice the difference because we feel better.
If we don’t eat enough fibre, the bacteria start eating the lining of our gut, a tasty mucous layer that’s vital for how our gut wall functions. The wall can then become inflamed and porous, leading to problems like leaky gut and colitis. Ouch!
Fibre Sometimes Makes Things Worse
We need enough of the right kinds of friendly bacteria to break down fibre. If we don’t have enough, what happens to the fibre we eat? It just irritates our gut and makes things worse.
That’s why gastroenterologists sometimes recommend low fibre diets to patients with Irritable Bowel Syndrome (IBS, one of the most common and least understood gut problems).
If your gut is in a bad state this can be very confusing. You faithfully follow the standard advice and eat high fibre food, maybe a big bowl of All Bran or oats, and what happens? Your symptoms get worse: misery ensues.
How Do I Train My Friendly Bacteria to Cope With More Fibre?
So what should we do? For a start, it’s better to get your fibre from fruit and veggies rather than from processed breakfast cereals that are full of irritants like high-fructose corn syrup and gluten.
As your gut starts to gradually recover over the course of weeks and months, you can gradually start increasing your fibre intake. If this causes a flare up of your symptoms, decrease or stop the fibre, then try again the following week.
The 3 Things You Need To Know:
- We can’t digest fibre. Without bacteria to break it down, fibre passes straight through us.
- Fibre feeds and nurtures our friendly bacteria, and they’re super important to our health
- If we don’t have enough of those helpful bacteria, eating fibre can make our symptoms worse.