Medical Specialties: Family practice, Internal medicine, Pediatrics, Other

Clinical Definition

Anemia is a blood disorder that occurs when a person does not have adequate hemoglobin, which transports oxygen through the body, via the blood. Anemia is frequently caused from a lack of iron, which the body uses to make hemoglobin. More serious types of anemia are sickle-cell anemia, which is an inherited disease whereby the red blood cells are sickle shaped. In sickle cell anemia, the sickle-shaped cells causes blood vessels to be clogged easily.

In Our Own Words

Anemia is a blood disorder that is most commonly caused by iron deficiency either from blood loss, or a lack of iron in a person's diet. Without iron, the body does not produce enough hemoglobin, a substance in the red blood cells that helps transport oxygen throughout the body.


While iron deficiency is most common, a vast number of other conditions can lead to anemia. Nutritional deficiencies, cancer, inherited genetic defects, medication-related side effects, and chronic diseases can all lead to anemia. It can also occur because of blood loss from injury or internal bleeding, the destruction of red blood cells, or insufficient red blood cell production. The condition may be temporary or long-term, and can manifest in mild or severe forms.

Relevant Conditions
  • Iron deficiency
  • Vitamin deficiency
  • Pregnancy
  • Chronic disease
Common Types
  • Iron-deficiency anemia
  • Sickle cell anemia
  • Hemolytic anemia
Side Effects
  • Shortness of breath
  • Dizziness
  • Headache
  • Weakness and fatigue
  • Pallor (normal healthy red and pink hues subdued)
Share this article
Keep Reading

Investigate your bodys signs and signals.
Try Symptom Checker