Anemia

Anemia is a condition characterized by insufficient healthy red blood cells or hemoglobin to carry adequate oxygen to tissues. Iron-deficiency anemia is the most common type worldwide and a well-established cause of diffuse hair loss. Other nutritional anemias include megaloblastic anemia from vitamin B12 or folate deficiency. Symptoms include fatigue, pallor, shortness of breath, dizziness, and brittle nails. Hair loss from anemia is typically telogen effluvium and is reversible with correction of the underlying deficiency. Hemoglobin, ferritin, and transferrin saturation are key diagnostic markers.