Runner's anemia and iron deficiency.

Systemic iron deficiency was found in 63 (56%) of 113 joggers and competition runners (33 women and 80 men). Thirteen women and ten men had latent anemia. A majority of the women were fertile with iron loss from menstruation; the men were runners training long distances. The average transferrin iron-binding capacity was 80 mu mol/l serum in the women and 77 (iron-binding groups) in the men. The haptoglobin and iron concentrations in serum were remarkably low (most often below 10 and 20 mu mol/l, respectively). Three of the long-distance runners ran 25 km daily. They returned with so much free hemoglobin in their plasma that an accompanying iron loss (integrated over months), if not balanced by diet, would lead to iron deficiency and anemia. Oral iron therapy (200 mg ferrous sulphate per day) normalized the hemoglobin concentration and improved the transferrin saturation fraction in 61 persons. The competition runners reported personal records.