GSTM1 and anemia (phenotype): At baseline, the prevalence of anemia (Hb <120 g/L) was 17% (n = 25/144), ID based on inflammation-adjusted ferritin <15 μg/L was 6% (n = 9/144), and ID anemia based on inflammation-adjusted ferritin <15 μg/L and Hb <120 g/L was 3% (n = 5/144).