Adaptation of iron bioavailability with high phytate diet consumption (122.6)

Abstract

Phytate is one of the inhibitors of nonheme iron absorption which is of particular concern in developing countries. In this study, we investigated whether individuals adapt to the inhibitory effect of phytate on iron bioavailability. Female subjects with Ferritin < 30µg/L (n=28) were randomized into two groups of 14 after matching for ferritin. Each group consumed either high or low phytate foods that were provided for 8 weeks. Iron bioavailability from a high phytate test meal was measured using area under the curve (AUC) for serum iron at baseline and after the intervention. During the 8 week period, phytate intake increased significantly (p<0.01) in the high phytate (HP) group and decreased significantly (p<0.001) in the low phytate (LP) group. No significant changes were observed in ferritin and transferrin receptor concentrations in both groups. AUC increased significantly (p<0.05) in the HP group (640 to 905 µmol/L) but the decrease (337 to 267 µmol/L) in the LP group was not significant. We found a strong positive correlation between phytate intake and AUC (r=0.68, p<0.0001) and a negative correlation between hepcidin and AUC at post intervention (r= ‐0.48; p=0.011). Our data suggests that iron bioavailability from high phytate meal may improve in individuals who consume a habitual high phytate diet. Further studies on how long term dietary changes affect the regulation of iron absorption are needed.Grant Funding Source: IFPRI/HarvestPlus