Anaemia is functionally defined as an insufficient RBC mass to adequately deliver oxygen to peripheral tissues, thereby causing tissue hypoxia. Although red cell mass is the gold standard in the assessment of anaemia, its measurement is cumbersome and rarely performed outside of clinical research. Anaemia can also be defined as a reduction in haemoglobin (Hb) concentration, haematocrit or number of RBCs per cubic millimetre. As per the World Health Organization (WHO), the haemoglobin threshold for children aged 5.00 to 11.99 years is 11.5 g/dl and for children aged 12.00-14.99 years is 12.0 g/dl.
Iron deficiency is the most common nutritional deficiency in the world; responsible for a staggering amount of ill health, lost productivity, and premature death.
Iron is necessary for production of haemoglobin which contains more than one-half of the total-body iron. The demands for iron during erythropoiesis are created by three variables: tissue oxygenation, erythrocyte turnover, and erythrocyte loss from haemorrhage.