The MAL-ED study (Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health) followed a cohort of 1283 children ages 9 to 15 months from eight low resource populations to determine their risk of anemia, low retinol, zinc, ferritin, and high transferrin receptor (TfR) [69]. Here, TFRC is linked to nutritional deficiency disease.