Zinc bioavailability in young adult rats fed sweet potato greens containing phytic acid.

This study determined whether phytic acid in sweet potato greens influences the bioavailability of zinc in young adult rats used as models for adult humans. A control diet (AIN-93M), two AIN-93M diets with pure phytic acid (PA) at 0.2% or 0.4%, and four diets with Georgia Jet or TU-82-155 dried blanched greens at 7.5% or 15% were fed to seven groups of 7-week male Harlan-Sprague rats for 21 days. Weight gains were generally not affected by PA concentration, were lower in the rats fed with sweet potato greens than in the control rats, and were similar in the rats fed with pure PA or control diet. Feed intake utilization, as indicated by the total weight gain per total feed intake, was almost similar in the different rat groups. Bone (femur, tibia) and organ (kidney, liver, lung, spleen) weights, except the heart weights, were similar for all diet groups. Their zinc concentrations were generally not affected by PA concentration but depended on the PA source.