GSTM1 and anemia (phenotype): Based on the mean final Hb values at 14 d, the HRE ratio of the 12 mg iron/kg diet was significantly higher (p ≤ 0.05) compared to the other HIP diet groups; however, only the HIP provided in the 36 and 48 mg iron/kg diets restored hemoglobin to high enough levels (mean Hb > 6 g/dL) to correct anemia.