GSTM1 and anemia: Iron deficiency anemia was seen among 2.14% of regular donors in comparison to another survey in Iran that observed iron deficiency anemia among 16% of regular male donors,[1] a quite lower figure, but it is pretty comparable to a survey in Denmark, with ferritin less than 15, Hb lower than 12.9 and also ferritin less than 15, Hb lower than 13.7, rate of iron deficiency anemia among males recorded at 0.26% and 0.5% respectively.[8]