Iron Deficiency Anemia



Iron deficiency anemia is caused by low levels of iron in the body. Iron is needed to build healthy RBCs. Low iron levels may be caused by one or more of these issues:

  • Problems with iron getting from the stomach or intestines into the blood due to intestinal diseases or surgery
  • Chronic bleeding.
  • Not enough iron in the body—a common cause in infants, children, and pregnant women

Risk Factors

Things that may increase the chance of iron deficiency anemia are:

  • Growth spurts that can happen in infants, children, and teens
  • Heavy menstrual bleeding
  • Health issues that cause bleeding in the gastrointestinal tract
  • Pregnancy
  • Breastfed infants who have not started on solid food after 6 months of age
  • Babies who are given cow’s milk before 12 months of age
  • Alcohol use disorder
  • Diets that do not have enough iron—rare in the US



People with this type of anemia may have:

  • Fatigue or weakness
  • Pale skin, fingernail changes, or hair loss
  • Headache
  • Rapid heartbeat
  • A craving for things that are not food, such as clay
  • Shortness of breath during or after physical activity
  • Restless legs at night

Mild anemia may not cause problems.


The doctor will ask about symptoms and past health. A physical exam will be done. Blood tests will be used to confirm anemia. It will also show problems with the level of iron. Other tests may be done to look for a cause.



The goal of treatment is to bring iron levels back to normal. The body will then be able to make more RBCs. This can be done by:

  • Treating underlying causes, such as:
    • Slowing or stopping blood loss to stop the loss of iron and let iron levels recover
    • Treating intestinal health problems to allow them to pass iron to the rest of the body
  • Taking an iron supplement by injection or pill to increase the volume of iron that gets into the blood.
  • Having babies eat iron fortified foods, such as cereal.


Adults can lower the risk of iron deficiency anemia by eating foods that are rich in iron, such as meat, poultry, fish, peas, beans, and potatoes.

The risk of iron deficiency anemia in babies can be lowered by giving:

  • Premature infants an iron supplement starting at 1 month of age until they start on a formula fortified with iron
  • Breastfed infants an iron supplement starting at 4 months of age
  • Bottle fed infants a formula fortified with iron starting at 4 months of age

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.