Dietary fibre is not a single ingredient. It is a family of carbohydrates that the small intestine does not fully digest. Some types hold water; some are fermented by gut bacteria; the mix depends on the plants you eat.
Australian Nutrient Reference Values set adequate intakes for adults well above what many people typically record. The practical sources are ordinary: oats, grainy bread, lentils, chickpeas, beans, vegetables with the skin on, fruit, nuts and seeds. Ultra-processed snacks can be high in energy and still low in fibre.
Increasing fibre works better when fluids increase with it, and when the change is gradual. A sudden jump from a low-fibre pattern can be uncomfortable. Looking at a week of meals — how often legumes appear, whether breakfast includes a grain — is more informative than a fibre number taken from one labelled bar.
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