With the objective of restoring the low zinc bioavailability of phytate-containing diets, cellulose was replaced by pectin, alginic acid, carrageenan, chitosan or raw potato starch (RS), in phytate-free and phytate-containing diets, and given to rats for 21 days. Feeding chitosan, alginic acid or RS (200 g/kg) as the dietary fiber polysaccharide lessened the deleterious effect of phytate, increasing zinc apparent absorption (excluding RS), femur zinc concentration and growth, compared to rats fed cellulose or fiber-free diets. Feeding pectin, alginic acid, chitosan or RS (200 g/kg) lowered cecal pH and increased cecal content weight. Chitosan, alginic acid and RS increased femur zinc concentration when fed to rats in phytate-containing diets, while RS was also effective in phytate-free diets. Therefore, chitosan and alginic acid might enhance zinc bioavailability through a different mechanism from that of RS. Feeding chitosan, alginic acid or raw potato starch lessens the inhibitory effect of phytic acid on zinc bioavailability.