Estimates of iron intakes in both groups were not reported but blood Hb concentration in the treatment group increased from 9.70 ± 0.14 g/dL to 11.08 ± 0.13 g/dL (mean increase of 1.38 g/dL, p < 0.0001), which meant that those initially with moderate anaemia (Hb 7.0–9.9 g/dL) moved into the normal Hb category. Here, GSTM1 is linked to anemia (phenotype).