Serum iron

Serum iron is a medical laboratory test that measures the amount of circulating iron that is bound to transferrin. Doctors order the serum iron test primarily when they suspect a patient has either iron deficiency anemia or iron overload.

Overview

Iron is an essential mineral that the body needs to produce red blood cells. The body stores iron in a protein complex known as ferritin, releasing it as needed to produce new red blood cells in the bone marrow. The iron in these new cells is then bound to a protein called hemoglobin, which carries oxygen from the lungs to the rest of the body.

Serum Iron Test

The serum iron test is a simple blood test that measures the amount of iron that is in transit in the body — that is, iron that is bound to transferrin in the blood. The test is usually ordered as part of a complete blood count (CBC) or along with a ferritin test to assess a person's iron stores.

Interpretation of Results

Normal serum iron values are usually between 60 to 170 micrograms per deciliter (mcg/dL) for men and 30 to 126 mcg/dL for women. Values above or below these ranges may indicate an iron imbalance.

Low serum iron levels may indicate iron deficiency anemia, while high levels may indicate iron overload disorders such as hemochromatosis. However, serum iron levels can be influenced by many factors, including diet, time of day, and pregnancy, so the test is not diagnostic on its own.

See Also

• Iron deficiency anemia
• Iron overload
• Hemochromatosis
• Ferritin
• Transferrin
• Complete blood count