Most of us grew up hearing that fibre was “good for digestion”.
That is true — but fibre does much more than that.
Fibre can help:
- keep you full for longer
- steady blood sugar
- feed gut bacteria
- lower cholesterol
- help regular bowel movements
- reduce constipation
This is especially important for people taking GLP-1 weight-loss drugs such as Ozempic, Wegovy or Mounjaro, which commonly slow digestion.
The Different Types of Fibre
Soluble Fibre — The “Gel” Fibre
This fibre absorbs water and forms a soft gel in the gut.
It helps:
- slow digestion
- steady hunger
- reduce sugar spikes and crashes
- soften stools
Foods high in soluble fibre include:
- oats
- beans
- lentils
- chia seeds
- apples
- citrus fruits
Because it holds water, fluid intake matters.
Think about oats or chia seeds sitting in liquid — they swell and thicken. Something similar happens in the gut. Without enough fluid, fibre can actually make bloating or constipation worse.
This is also worth remembering with high-fibre drinks or “fibre sodas”. Added fibre may increase your need for fluids rather than replacing them.
Insoluble Fibre — The “Broom” Fibre
This type adds bulk and helps keep food moving through the digestive system.
You find it in:
- whole grains
- bran
- nuts
- seeds
- vegetable skins
- leafy vegetables
Resistant Starch — The “Slow Burner”
Some starches behave more like fibre and help feed gut bacteria.
Sources include:
- beans and lentils
- cooked and cooled potatoes
- cooked and cooled rice
- green bananas
- oats
What About Added Fibre?
You now see fibre added to:
- snack bars
- yoghurts
- cereals
- powders
- drinks
Some isolated fibres genuinely help. Psyllium, for example, has good evidence for constipation.
But a fibre soda is not the same as eating real plant foods.
Whole foods bring:
- different fibre types
- vitamins and minerals
- plant compounds
- slower digestion
- better fullness
Scientists increasingly think this whole “food package” matters.
Fibre and GLP-1 Drugs
GLP-1 drugs help people feel fuller partly because food leaves the stomach more slowly.
Interestingly, soluble fibre creates a milder version of this naturally:
- digestion slows
- hunger is delayed
- energy release becomes steadier
- snacking may reduce
This does not mean fibre works like a drug. But it may help people build eating habits that continue working after medication stops.
And perhaps the best bit is this:
Real food starts tasting good again.
Many processed foods are carefully engineered around combinations of sugar, salt and fat — sometimes called the “bliss point” — which encourages overeating.
Many people on GLP-1 drugs notice that ultra-processed foods become less appealing. That can create space to rediscover:
- beans
- lentils
- fruit
- herbs and spices
- proper meals made from real ingredients
Over time, a varied fibre-rich diet may help shift appetite away from constant processed snacking toward foods that actually leave you satisfied.
Water Matters Too
When increasing fibre intake, fluids matter too.
Soluble fibre absorbs water and thickens digestion. That is part of why it helps with fullness and steadier energy release — but without enough fluid it can also make constipation worse.
The simple rule:
- increase fibre gradually
- drink more water
- aim for variety rather than extremes
What This Means Practically
You probably do not need expensive supplements or “gut detoxes”.
For most people, the basics work surprisingly well:
- add beans to meals
- eat more oats
- swap some white grains for wholegrains
- add seeds to breakfast
- increase plant variety gradually
- drink enough fluid
Your gut bacteria like variety far more than perfection.