Effects of moderate iron supplementation on the iron status of runners with low serum ferritin

Twenty-four of 75 women and 8 of 121 men screened at a Marathon Fitness Exposition had serum ferritin concentrations less than 20 ng/ml, indicating iron deficiency. The highest incidence of low serum ferritins was in women, aged 20-29 years (41%) and older than 50 years (37%). Four months later, 16 women and 6 men with ferritins less than 30 ng/ml received 120 mg of supplemental iron for 7 weeks. Serum ferritins increased significantly from 14±9 to 26±13 ng/ml after supplementation for women, and from 18±14 to 29±12 ng/ml for men. Hemoglobin concentrations increased significantly in men from 13.6±0.3 to 14.0±0.6 g/dl. Dietary intakes of protein and ascorbic acid were adequate while calories and iron tended to be low. Thus, about one-third of active women and 7% of active men screened at a Fitness Exposition had serum ferritin concentrations less than 20 ng/ml. Supplemental iron improved serum ferritin values in women and men, and hemoglobin levels in men.