Current data with inulin-type fructans and calcium, targeting bone health in adults

In humans, there is increasing evidence that the colon can absorb nutritionally significant amounts of calcium, and this process may be susceptible to dietary manipulation by fermentable substrates, especially inulin-type fructans. Inulin-type fructans can modulate calcium absorption because they are resistant to hydrolysis by mammalian enzymes and are fermented in the large intestine to produce short-chain fatty acids, which in turn reduce luminal pH and modify calcium speciation, and hence solubility, or exert a direct effect on the mucosal transport pathway. Quite a few intervention studies showed an improvement of calcium absorption in adolescents or young adults by inulin-type fructans. In the same way, a positive effect has been reported in older women.