Anemia
A blood disorder reducing oxygen transport, affecting billions worldwide.
Anemia is a blood disorder characterized by a reduced ability of the blood to carry oxygen, due to a lower number of red blood cells, reduced hemoglobin, or hemoglobin abnormalities. It is the most common blood disorder, affecting about a fifth to a third of the global population, and can range from mild to severe, temporary or long-term.
Quick Facts
- Field
- Hematology
- Symptoms
- Feeling tired
- pale skin
- weakness
- shortness of breath
- feeling faint
- Causes
- Blood loss
- decreased red blood cell production
- increased red blood cell breakdown
- Diagnosis
- Blood hemoglobin measurement
- Frequency
- 1.92 billion; 24% (2021)
Facts from the source article.
Lore & Background
Anemia happens when the body’s blood can’t carry enough oxygen. This can come from blood loss, like heavy periods, stomach bleeding, surgery, injury, or donating blood. It can also come from not making enough red blood cells, due to low iron, folate, or vitamin B12, or from conditions like thalassemia and bone marrow tumors. Another cause is red blood cells breaking down too fast, which happens with sickle cell disease, malaria, or certain autoimmune disorders.
Did You Know?
- Iron-deficiency anemia is the most common cause worldwide, affecting nearly one billion people.
- In 2025, the WHO noted a 35.5% anemia rate in pregnant women, compared to 30.5% in non-pregnant women.
- The name derives from Ancient Greek 'an-' (not) and 'haîma' (blood).
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