REF-340 · Sim et al., 2019 / Pedlar et al., 2018 · Sim: European Journal of Applied Physiology · Paper
Iron considerations for the athlete: a narrative review
Iron deficiency in ~15-35% of female and ~5-11% of male athlete cohorts; exercise-induced hepcidin is a key driver, with sex hormones, diet, training and altitude all shaping iron status
Key Findings (Sim 2019 abstract)
Iron is central to oxygen transport and energy metabolism; athlete populations, especially females and endurance athletes, are commonly diagnosed with iron deficiency.
Prevalence: iron deficiency is most common in female athletes (~15-35% of athlete cohorts deficient), and approximately 5-11% of male athlete cohorts also present with it.
Exercise-induced increases in hepcidin, the master iron-regulatory hormone, are highlighted as a contributing factor to altered iron metabolism in athletes.
The review covers how sex hormones, diet (e.g., macronutrient manipulation), training and environmental stress (hypoxia from altitude training) affect an athlete's iron status, and draws recommendations for future work.
The abstract gives no ferritin thresholds, dosing regimens, absorption windows or menstrual-loss figures.
Practical Application
This narrative review reports that iron deficiency is common in athletes — about 15-35% of female athlete cohorts and 5-11% of male cohorts — and that exercise-induced rises in hepcidin, the master iron-regulating hormone, are a contributing factor, with sex hormones, diet, training and altitude exposure all shaping iron status. So a female endurance athlete, anyone with heavy training or a coming altitude block, should have iron status measured rather than assumed — and a male athlete is not exempt.
Inference, not tested here: because hepcidin rises after exercise and hepcidin blocks absorption, the base's habit of taking iron away from hard sessions follows from the mechanism the review names; the exact window is not given in the abstract.
Not from this paper; the base's own practice: screening panel (ferritin, haemoglobin, transferrin saturation) at the start of a block, alternate-day morning dosing with vitamin C and away from tea, coffee and calcium, and re-testing during heavy blocks are house practice; the pre-altitude ferritin targets the base uses are in SYNTH-06.
Limitations
Narrative review: the prevalence figures are cohort ranges, not a pooled estimate; no effect sizes for supplementation are in the abstract.
Ferritin is an acute-phase reactant; inflammation (post-HIT, illness) raises it — interpret with CRP (base's own practice, not from this abstract).
The Pedlar 2018 identifier (10.1080/17461391.2017.1416189) returned "not found" on Crossref and Europe PMC on 2026-09-27; nothing in this entry rests on it. Not changed here — flagged for the KB owner.
How this entry was checked and changed
Why this level
regraded 2026-09-27 from A: narrative review without systematic method, from the leading athlete-iron research group
Content correction 2026-09-27
"3-11% in males" -> 5-11% (abstract).
"Menstrual losses 5-15 mg/cycle, 30+ mg", "hepcidin spike 3-6 h", ferritin thresholds "<20 / 20-35 / ≥35-50 ng/mL", "Hb <120 g/L", "65-200 mg elemental Fe, alternate-day superior (Stoffel 2017)", "separate calcium by 2 h", "altitude iron demand 2-3×", "re-test every 3 months" -> none of these figures are in the abstract; removed or reduced to unnumbered house practice with a pointer to SYNTH-06.
Level A -> B+ (narrative review). Title now names the paper.