Anemia is a low level of healthy red blood cells (RBC). RBCs carry oxygen from the lungs to the rest of the body. Iron is needed to build healthy RBCs. Lower RBC counts mean the body is not getting enough oxygen.

Red Blood Cells
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Iron makes a critical component of red blood cells.
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Factors that play a role include:

  • Iron that is poorly absorbed in the digestive tract—may occur due to intestinal diseases or surgery
  • Chronic bleeding , such as heavy menstrual bleeding or bleeding in the gastrointestinal (GI) tract
  • Not enough iron in the diet—common cause in infants, children, and pregnant women