Most gut problems are a fibre problem wearing a probiotic costume

The CFU number problem

Thirty billion colony-forming units sounds decisive. Your colon already contains something on the order of a hundred trillion organisms. The arithmetic is unkind: a daily probiotic dose is a rounding error against the resident population, and most strains are transient — they pass through without colonising.

That does not make probiotics useless. It makes them a narrow tool, useful for specific strains against specific conditions, and a poor first choice for general digestive complaint.

Substrate beats settlers

If you want more of the bacteria that produce short-chain fatty acids, the reliable route is to feed the ones you already have. Fermentable fibre — inulin, GOS, resistant starch — does that. The population shift is measurable within weeks and it is your own microbiome, adapted to you.

This is also why fibre changes appetite and glucose handling, not just regularity. Short-chain fatty acids signal satiety through the same pathways the newer weight drugs target pharmacologically.

Both kinds, at food-level doses

Soluble fibre ferments and feeds. Insoluble fibre adds bulk and speeds transit. Constipation usually responds to both together, and to neither alone in a 500 mg capsule.

Adults need somewhere near 25 to 30 grams of total fibre daily. Most people in cities eat half that. A supplement is closing a gap of ten to fifteen grams, which is why real fibre products come as sachets, not tablets.

How to start without the discomfort

Bloating and wind in the first week are a fermentation adjustment, not an intolerance. Start at half a dose for three days, take it with a full glass of water, and increase once it settles.

If discomfort persists past two weeks, or if you have a diagnosed motility disorder or IBS with a known FODMAP trigger, speak to a clinician before continuing. Inulin is a FODMAP, and for a minority of people it is genuinely the wrong fibre.