Ifayibha yokutya luhlobo lokutya olungenakophulwa yi-enzymes yokugaya umzimba womntu, ayikwazi ukufunxwa ngumzimba wezinto ze-polysaccharide kunye negama eliqhelekileyo le-lignin.
Nangona inomahluko ocacileyo kunye neprotheyini, amafutha, iivithamini kunye nezinye izondlo, ibaluleke kakhulu kwimpilo yabantu, kude kube ngo-1970, i-fiber yokutya yaziswa ngokusemthethweni kuluntu lwezondlo, ihlelwa njenge "isondlo sesixhenxe", kwaye emva koko imarike yabonisa ukukhula okulungileyo.