Iron is an essential nutrient that, among other functions, is needed in small quantities to help form normal red blood cells (RBCs). It is a critical part of hemoglobin, the protein in RBCs that binds oxygen in the lungs and releases it as blood circulates to other parts of the body. The body cannot produce iron and must absorb it from the foods we eat or from supplements.
TIBC (total iron-binding capacity)—measures the total amount of iron that can be bound by proteins in the blood. Transferrin is the protein that transports iron around in the body. Under normal conditions, transferrin is typically one-third saturated with iron.
Serum ferritin—reflects the amount of stored iron in the body
