Alternate-Day, Low-Dose Oral Iron Supplementation and Hepcidin-Guided Dosing Timing in Athletes: A Narrative Review
DOI:
https://doi.org/10.12775/QS.2026.71.74800Keywords
iron deficiency, iron supplementation, hepcidin, athletes, alternate-day dosing, oral iron, endurance athletesAbstract
Introduction: Iron deficiency is one of the most common micronutrient deficiencies in athletes, particularly in endurance athletes and women. The effectiveness of oral iron supplementation depends not only on the dose but also on supplementation timing, dosing frequency, and hepcidin regulation.
Aim: To summarize current evidence on oral iron supplementation strategies in athletes, with particular emphasis on the role of hepcidin in optimizing iron absorption.
Material and methods: A literature search was conducted through PubMed (MEDLINE) and Google Scholar. Randomized controlled trials, stable-isotope studies, and review articles published in English up to February 2026 were analyzed.
Results: Current evidence suggests that alternate-day, low-dose oral iron supplementation improves gastrointestinal tolerance and may enhance iron absorption compared with daily dosing. Iron absorption is influenced by circadian rhythm and exercise-induced increases in hepcidin, making supplementation timing clinically important. Conventional ferrous salts remain the first-line treatment, whereas novel formulations and intravenous iron may be appropriate in selected cases.
Conclusions: Iron supplementation should be individualized according to iron status, training schedule, treatment tolerance, and clinical needs. Optimizing dosing frequency and timing represents a simple strategy to improve treatment effectiveness. Further athlete-specific studies are needed to establish evidence-based recommendations.
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Copyright (c) 2026 Julia Obersztyn, Adrianna Szczecińska, Hubert Kulawinek, Aleksandra Mliczek, Grzegorz Kasparek, Krzysztof Maksym Kasparek, Wiktoria Glanert, Jakub Maksymilian Bajer, Piotr Mrozek, Marta Czech
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