GSTM1 and anemia (phenotype): Multinomial logistic regression with normal Hb concentrations as reference, showed highly significant (p<0.001) associations between women who were underweight and those with moderate/severe anaemia (risk ratio (RR): 1.9, 95% CI 1.6 to 2.2) as well as those with mild anaemia (RR: 1.3, 95% CI 1.2 to 1.5).