Can iron deficiency anaemia cause shortness of breath?

Iron is needed to make haemoglobin, the part of red blood cells that carries oxygen. When iron stores are low enough to cause anaemia, your heart and breathing muscles may work harder to meet the body's oxygen needs. You may notice breathlessness when walking quickly, climbing stairs or exercising, along with tiredness, dizziness, paler skin or a fast heartbeat. Breathlessness has many possible causes, so this symptom alone cannot identify iron deficiency anaemia.

Arrange a clinical assessment if breathlessness is new, persistent or limiting your usual activities. A clinician may ask about diet, menstrual or other bleeding, bowel symptoms and medicines, then use blood tests to check haemoglobin and iron stores. Do not start iron tablets solely because you feel breathless; taking iron when it is not needed can cause side effects and may delay finding another cause. If iron deficiency is confirmed, treatment also needs to address why your iron became low.

Seek emergency help for severe or rapidly worsening breathlessness, breathing difficulty at rest, chest pressure, fainting, blue or grey lips, confusion or coughing up blood. Prompt medical review is also sensible when breathlessness comes with black or bloody stools, heavy ongoing bleeding or marked weakness.

Ask whether blood tests should include a full blood count and iron studies, what may be causing low iron, and how your breathing symptoms will be monitored. You can also ask which warning signs should prompt urgent review.