Effect of Difference in Chemical Species of Dietary Iron on Iron Status in Rats

Abstract

Four-week-old male Wistar rats were fed a AIN93G-based diet containing iron at a level of 20 μg/g as ferrous sulfate, ferric citrate, pig hemoglobin or a processed low-molecular-weight (LMW) heme iron for 4 weeks and effect of the difference in dietary iron source on iron nutritional status was examined. The highest iron contents in liver, kidney, small intestine, spleen and femur were observed in rats fed the diet containing ferrous sulfate. In the hemoglobin, hematocrit and serum iron, the highest values were also observed in the rats given ferrous sulfate, while the lowest values were observed in the rats given the LMW heme iron. Apparent iron absorption of the rats given ferrous sulfate or hemoglobin were 52 to 60 %, whereas that of the rats given ferric citrate or the LMW heme iron were 20 to 26 %. These results indicate that iron bioavailability of hemoglobin is lower than ferrous sulfate in rats and that of the processed LMW heme iron is lower than intact hemoglobin or ferric citrate.