We evaluated the effects of regular physical exercise on anemia and iron status in young non-professional female athletes. A total of 191 healthy white Italian women (23.5 +/- 4.68 years) were analyzed; 70 were non-professional athletes performing 11.1 +/- 2.63 h week(-1) exercise and 121 were sedentary controls. Blood markers of anemia and iron status-hemoglobin (Hb), hematocrit (Hct), red blood cells (RBC), serum ferritin, iron, transferrin (Tf), transferrin saturation (TfS), soluble transferrin receptor (sTfR), and the sTfR/log ferritin ratio (sTfR-F index)-were evaluated. Anemia threshold was Hb < 120 g l(-1). Ferritin concentrations < 12 microg l(-1) were considered as iron deficiency (ID). Frequency of anemia (15.7 versus 10.7%, P = 0.32), ID (27.1 versus 29.8%, P = 0.70), and ID anemia (8.6 versus 5.8%, P = 0.46) was not different in athletes and controls. However, athletes were threefold more likely than controls (17.1 versus 5.8%) to have serum iron < 50 microg dl(-1) [odds ratio (OR) 3.37, P = 0.012]. Low-TfS (<15%) was found in 25.7% of athletes and in 13.2% of controls, OR 2.27, P = 0.030. Elevated-sTfR (>1.76 mg l(-1)) was found in 24.3% of athletes and in 12.4% of controls, OR 2.27, P = 0.034. Regular non-professional sport activity does not cause an increased rate of anemia or of iron deficiency in fertile women. However, physical exercise has an impact on iron status as it reduces serum iron and transferrin saturation, and elevates sTfR. Nearly one fifth of recreational athletes have anemia and a third have iron deficit, these conditions can decrease their physical performance.