Data from the SANHANES study in 2012 support a low prevalence of iron deficiency since only 10.5% of 16–25 years old adolescents and women were found to have iron deficiency anemia (Hb ≤ 12 g/dL and ferritin ≤ 15 μg/L These results that point to adequate intakes prior to 2006 are not aligned with the estimation of iron deficiency anemia in South African children and adolescents of 25.5% by the Global Burden of Disease 2013 Study [31]. The gene discussed is GSTM1; the disease is nutritional disorder.