SynthesisSports health
Does Iron Supplementation Improve Performance in Iron-Deficient Nonanemic Athletes?
Synthesis in Sports health. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 37 papers, 4 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
37 citing papers in PubMed, 4 syntheses or guidelines pooled it, 80 citations in OpenAlex.
- Effects of dietary supplements on lower-limb power and jump performance in physically active individuals and athletes: a systematic review and Bayesian network meta-analysis.Journal of the International Society of Sports Nutrition · 2026Pooled it
- Systematic review and meta-analysis of intravenous iron therapy for adults with non-anaemic iron deficiency: An abridged Cochrane review.Journal of cachexia, sarcopenia and muscle · 2022Pooled it
- The association of HFE gene H63D polymorphism with endurance athlete status and aerobic capacity: novel findings and a meta-analysis.European journal of applied physiology · 2020Pooled it
- The Role of Mineral and Trace Element Supplementation in Exercise and Athletic Performance: A Systematic Review.Nutrients · 2019Pooled it
- Dose-Dependent Alterations of the Human Gut Microbiome During Oral Iron Supplementation: A Randomized Study in Iron-Deficient Non-Anaemic Women.Nutrients · 2026Trial
- Iron deficiency in young basketball players: Is a 100 μg/L ferritin cut-off appropriate for iron supplementation?: Results of a randomized placebo-controlled study.Clinical cardiology · 2023Trial
- The Effect ofNutrients · 2020Trial
- Relationship Between Blood Creatine Kinase and Muscle Damage in Speed Skaters.Journal of musculoskeletal & neuronal interactions · 2026Article
- Potential Usefulness of Urinary Hepcidin Measurement for Iron Deficiency Anemia in Female Athletes.European journal of sport science · 2026Article
- Improvements in competition performance of national-level track and field athletes following a personalized nutrition intervention: a mixed methods approach.BMC sports science, medicine & rehabilitation · 2025Article
- Article
- Effect of baseline ferritin levels on post-exercise iron metabolism in male elite youth rowers.Scientific reports · 2025Article
- Article
- Unlocking the connection: hematological status, dietary iron intake and endurance in Indian female athletes.Physical activity and nutrition · 2025Article
- Efficacy of iron supplementation on physical capacity in non-anaemic iron-deficient individuals: protocol for an individual patient data meta-analysis.Systematic reviews · 2024Article
- Effect of Off-Season Iron Supplementation on Aerobic Capacity of Female Handball Player: A Randomized, Double-Blinded, Placebo-Controlled Study.Current developments in nutrition · 2024Article
- Sex differences in iron status during military training: a prospective cohort study of longitudinal changes and associations with endurance performance and musculoskeletal outcomes.The British journal of nutrition · 2024Article
- Female Athlete Triad and Relative Energy Deficiency in Sport (REDs): Nutritional Management.Nutrients · 2024Review
- Longitudinal changes in anthropometric, physiological, and physical qualities of international women's rugby league players.PloS one · 2024Article
- Prevalence of iron-deficient but non-anemic university athletes in Japan: an observational cohort study.Journal of the International Society of Sports Nutrition · 2023Observational
Corrections and comments
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Authors and funding
4 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
contextSupplementing iron-deficient nonanemic (IDNA) athletes with iron to improve performance is a trend in endurance sports.
objectivesTo investigate the benefits of iron on performance, identify a ferritin level cutoff in IDNA athletes, and determine which iron supplementation regimens are most effective. DATA SOURCES: A search of the PubMed, CINAHL, Embase, ERIC, and Cochrane databases was performed in 2014 including all articles. Citations of pertinent review articles were also searched. In 2017, the search was repeated. STUDY SELECTION: Inclusion criteria comprised studies of level 1 to 3 evidence, written in the English language, that researched iron supplementation in nonanemic athletes and reported performance outcomes. STUDY
designSystematic review. LEVEL OF EVIDENCE: Level 3. DATA EXTRACTION: The search terms used included athletic performance, resistance training, athletes, physical endurance, iron, iron deficiency, supplement, non-anemic, low ferritin, ferritin, ferritin blood level, athletes, and sports.
resultsA total of 1884 studies were identified through the initial database search, and 13 were identified through searching references of relevant review articles. A subsequent database search identified 46 studies. Following exclusions, 12 studies with a total of 283 participants were included. Supplementing IDNA athletes with iron improved performance in 6 studies (146 participants) and did not improve performance in the other 6 studies (137 participants). In the 6 studies that showed improved performance with iron supplementation, all used a ferritin level cutoff of ≤20 μg/L for treatment. Additionally, all studies that showed improved performance used oral iron as a supplement.
conclusionThe evidence is equivocal as to whether iron supplementation in IDNA athletes improves athletic performance. Supplementing athletes with ferritin levels <20 μg/L may be more beneficial than supplementing athletes with higher baseline ferritin levels.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.