The price of blood is measured in iron

Volunteer blood donors give about 500 mL of whole blood, approximately 10% of their total blood volume. After removal of plasma during processing, each mL of packed red blood cells contains 1 mg of iron. Thus, 200–250 mg iron are removed from the donor at each donation depending on their haematocrit. Since average iron stores are only 250 mg in women and 1000 mg in men, repeated donation produces iron deficiency in many donors.1 Iron deficiency induced by blood donation has potential for untoward effects, including impaired neurocognitive development in teenagers or in the fetus of a donor who becomes pregnant.