Physiology and Behavior Group, Department of Agricultural and Food Sciences, ETH Zurich, Zurich, Switzerland.
Eur J Clin Nutr. 2010 May;64(5):490-4. doi: 10.1038/ejcn.2010.16. Epub 2010 Mar 3.
BACKGROUND/OBJECTIVES: Iron deficiency and anemia may impair athletic performance, and iron supplements are commonly consumed by athletes. However, iron overload should be avoided because of the possible long-term adverse health effects.
We investigated the iron status of 170 male and female recreational runners participating in the Zürich marathon. Iron deficiency was defined either as a plasma ferritin (PF) concentration <15 microg/l (iron depletion) or as the ratio of the concentrations of transferrin receptor (sTfR) to PF (sTfR:log(PF) index) of > or =4.5 (functional iron deficiency).
After excluding subjects with elevated C-reactive protein concentrations, iron overload was defined as PF >200 microg/l. Iron depletion was found in only 2 out of 127 men (1.6% of the male study population) and in 12 out of 43 (28.0%) women. Functional iron deficiency was found in 5 (3.9%) and 11 (25.5%) male and female athletes, respectively. Body iron stores, calculated from the sTfR/PF ratio, were significantly higher (P<0.001) among male compared with female marathon runners. Median PF among males was 104 microg/l, and the upper limit of the PF distribution in males was 628 microg/l. Iron overload was found in 19 out of 127 (15.0%) men but only 2 out of 43 in women (4.7%). Gender (male sex), but not age, was a predictor of higher PF (P<0.001).
Iron depletion was present in 28% of female runners but in <2% of males, whereas one in six male runners had signs of iron overload. Although iron supplements are widely used by athletes in an effort to increase performance, our findings indicate excess body iron may be common in male recreational runners and suggest supplements should only be used if tests of iron status indicate deficiency.
背景/目的：铁缺乏和贫血可能会影响运动员的表现，因此运动员通常会补充铁。然而，由于可能存在长期的不良健康影响，应避免铁过载。
我们调查了参加苏黎世马拉松的 170 名男性和女性业余跑步者的铁状况。铁缺乏症定义为血浆铁蛋白 (PF) 浓度<15μg/l（铁耗竭）或转铁蛋白受体 (sTfR) 与 PF 的浓度比 (sTfR:log(PF) 指数)≥4.5（功能性铁缺乏）。
在排除了 C-反应蛋白浓度升高的受试者后，将 PF>200μg/l 定义为铁过载。仅在 127 名男性中的 2 名（男性研究人群的 1.6%）和 43 名女性中的 12 名（28.0%）中发现铁耗竭。分别在 5 名（3.9%）和 11 名（25.5%）男性和女性运动员中发现功能性铁缺乏。从 sTfR/PF 比值计算得出的体铁储存量，男性明显高于女性马拉松运动员（P<0.001）。男性的 PF 中位数为 104μg/l，男性 PF 分布的上限为 628μg/l。127 名男性中有 19 名（15.0%）发现铁过载，而 43 名女性中仅有 2 名（4.7%）。性别（男性）而不是年龄是 PF 较高的预测因素（P<0.001）。
女性跑步者中有 28%存在铁耗竭，但男性中<2%存在铁耗竭，而有 1/6 的男性跑步者存在铁过载迹象。尽管运动员广泛使用铁补充剂来提高运动表现，但我们的研究结果表明，男性业余跑步者中可能普遍存在过量的体铁，这表明如果铁状态测试表明存在缺乏，才应使用补充剂。
