Over the last few years, the colon has come to be considered more and more as a central digestive organ. This is where bacterial fermentation takes place to eliminate the substrates, mostly carbohydrates, that have avoided digestion by human enzymes within the small intestine. Of these, fibre plays a prominent role. As a result of this colonic fermentation, short-chain fatty acids are created and these have an important function at the level of the colon (reduction in pH, trophic effect, energy production, etc.) and at the systemic level (lipid metabolism, glycaemic metabolism, etc.) No less important are the effects of this colonic metabolism of fibre on proliferation of bacteria, thus giving fibre probiotic effects.