Anaemia contributes significantly to the morbidity and mortality of a population.1,4,5 Appropriate diagnosis and treatment is imperative, and tests that are commonly used in the diagnostic work-up of anaemia, such as haemoglobin (Hb) and serum ferritin, are readily available.6 Despite this, identifying and treating iron deficiency anaemia (IDA) can be challenging, partly because ferritin can be elevated in inflammation. Here, GSTM1 is linked to anemia.