What is the best method for determining storage iron?

Determining storage iron in the body is most effectively assessed by measuring serum ferritin levels. Ferritin is a protein that stores iron, and its concentration in the serum reflects the amount of stored iron in the body. When the body's iron stores are adequate, ferritin levels will be higher; conversely, low ferritin levels indicate depleted iron stores, which is commonly seen in conditions like iron deficiency anemia.

Serum transferrin levels measure the transport protein for iron in the blood, rather than the actual stores of iron. This can give insight into iron transport and whether the body is in a state of deficiency or overload but does not directly reflect the total amount of stored iron.

Hemoglobin values indicate functional iron, as hemoglobin is the protein in red blood cells that carries oxygen. However, it does not provide any information regarding the body's stored iron levels.

Myoglobin values are related to muscle oxygen storage and are not pertinent when assessing total body iron stores, making it irrelevant for this context.

Thus, serum ferritin levels are the most reliable and direct indicator of iron storage in the body.