Prebiotics — Fibre That Feeds Your Microbes
The kinds of fibre that make your beneficial bacteria throw a dinner party and send back helpful molecules.
Prebiotics are substances — usually certain fibres or plant compounds — that your own enzymes can’t digest but your gut microbes adore. Classic examples include inulin (in chicory, onions, garlic), fructo‑oligosaccharides (in bananas, wheat, asparagus), and resistant starch (in cooled potatoes, oats, beans). They travel largely intact to the colon, where microbes ferment them into short-chain fatty acids and other metabolites you benefit from.
Think of prebiotics as curated grocery deliveries for your favourite microbial tenants. Different strains have different tastes: some specialise in inulin, others in resistant starch, others in the polyphenols from cocoa or berries. When you rotate through a variety of plant foods, you feed a broader slice of your microbiome, helping it stay diverse and resilient instead of dominated by a few loud species.
Prebiotic supplements (like chicory fibre powders) can be useful tools, especially when someone struggles to eat enough plants. But they can also be… gassy. A big sudden dose of fermentable fibre is like inviting a marching band into a quiet street: there will be noise. For many people, gradually increasing whole‑food sources — oats, beans, lentils, nuts, seeds, fruits, vegetables — is a gentler way to ramp things up.
Importantly, prebiotics and probiotics play well together. Probiotics add specific live microbes; prebiotics feed both them and your resident species. Together, they support SCFA production, gut barrier integrity, and more stable blood sugar and appetite signals. But prebiotics on their own, via boring plant diversity, already do a lot of quiet heavy lifting.
Why It Matters
Prebiotics explain why “eat more plants” is microbiome advice, not just micronutrient advice — you’re not only feeding yourself, you’re programming which microbes thrive inside you.
Closing Line
Every time you toss beans in a salad or add oats to breakfast, you’re sending a love letter to the microbes that keep your gut calm and your colon cells well‑fed.