Iron (Fe) Test

Test Overview

An iron test checks the amount of iron in the blood. Iron (Fe) is a mineral needed for hemoglobin, the protein in red blood cells that carries oxygen. Iron is also needed for energy, good muscle, and organ function.

About 70% of the body's iron is bound to hemoglobin in red blood cells, Opens dialog. The rest is bound to other proteins, such as transferrin or ferritin, or stored in body tissues. When red blood cells die, their iron is released and carried by transferrin to the bone marrow and to other organs such as the liver and spleen. In the bone marrow, iron is stored and used as needed to make new red blood cells.

The source of all the body's iron is food, such as liver and other meat, eggs, beans, and leafy green vegetables. The body needs more iron at times of growth (such as during adolescence), for pregnancy, during breastfeeding, or at times when there are low levels of iron in the body (such as after bleeding).

The iron test checks the:

  • Amount of iron in the blood.
  • Amount of iron bound to transferrin in the blood (serum).
  • Ability of the blood to bind to iron and carry it around the body. This value is called the total iron-binding capacity (TIBC).
  • Percentage of transferrin with iron bound to them. This value is called transferrin saturation.
Information about Iron (Fe) Test

Current as of: April 30, 2024

Author: Ignite Healthwise, LLC Staff

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