CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-08-17). The draft was written by AI, the existence of all 1 cited sources was verified at the original page, and the verdict passed blind grading and adversarial audit. Methodology v0.7.
Verdict No. 2706 · Search date 2026-08-17 · Methodology v0.7

Transdermal iron patch,
does it really help with Raising iron stores as effectively as oral iron?

30-Second Summary
D
Evidence Grade D · 28 · Safety caution
The iron patch did not raise iron stores as effectively as oral iron in the only human comparison
Local skin irritation and inappropriate iron use remain concerns. Suspected deficiency requires diagnosis, cause assessment, and laboratory follow-up rather than substitution of a patch for established treatment.
What the
research shows
The grade is D with 28 points. The claim concerns the delivery route, not whether iron itself works. In an eight-week nonrandomized parallel study that enrolled 29 athletes and analyzed ferritin in 28, oral iron produced serum ferritin 15.27 micrograms/L higher than the patch at week 6 (P=.019). The patch showed no beneficial iron-store effect.
What the
ads claim
Containing iron is not proof that a patch delivers enough iron through skin to increase body stores. In the available human comparison, oral iron increased stores and the patch did not.
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Useful facts when choosing a product

  • The study patch was labeled to contain 45 mg iron as iron bisglycinate and was worn eight hours nightly for eight weeks.
  • The comparator supplied 105 mg elemental oral iron plus 500 mg vitamin C, so route, dose, salt, and coingredient differed.
  • Verdicts 421, 1032, and 2293 concern oral iron and therefore answer different delivery questions.
Gap Measurement · Verdict 2706 · D 28
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

The 29 endurance runners with ferritin below 50 micrograms/L were described only as "participants were assigned" and "Participant groups were matched by sFer concentration"; they were not randomized into the oral (15) and patch (14) groups. One oral participant withdrew, leaving 14 per group for ferritin analysis. PatchMD Iron Plus supplied a labeled 45 mg iron patch for eight hours nightly, whereas the oral arm used ferrous sulfate providing 105 mg elemental iron plus 500 mg vitamin C. There are four avoidable defects: ① nonrandom assignment with residual confounding, ② the small sample of 29, ③ lack of masking, and ④ a nonequivalent comparison because iron salt, dose, and vitamin C differed between the oral and patch groups. The article carries no funding statement and no conflict-of-interest declaration; its Acknowledgments records only author contributions. The patch is identified solely as "(Iron Plus; PatchMD, Las Vegas, NV)", with no statement that the manufacturer provided it. Because no funding source could be established, funding independence is not counted as a strength. No trial registration number could be confirmed.

02

Why this is classified as D (28)

A single nonrandomized comparison failed to show patch efficacy comparable with oral iron; its four observational-study defects—nonrandom assignment, a 29-person sample, lack of masking, and a nonequivalent comparison—give B2; the article carries no funding statement, so public or nonprofit funding could not be established; and no validated clinical boundary excluded all benefit, giving D with 28 points.

Counterpoint. This verdict does not deny oral iron efficacy; it narrowly addresses the transdermal route.

Rejudgment record. Cross-check applied — Cross-checked the article and thesis for nonrandom allocation, 28-person analysis, ferritin results, unequal doses, absence of a funding statement and unconfirmed registration and PatchMD involvement

Scoring profile behind this grade
EndpointSSurrogate marker - laboratory or imaging measures
ReplicationR1Single confirmatory trial
IndependenceI1Mixed funding sources
Effect sizeE0Null
PrecisionC0The confidence interval leaves room for benefit

The scoring table and the verdict agree (D).

Sub-claim grades by effect

This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.

Effect (sub-claim)GradeBasis
The patch raises iron stores as effectively as oral ironDOral iron produced significantly higher ferritin at week 6 in the only comparison.
The patch avoids gastrointestinal adverse effects?Severe gastrointestinal complaints were fewer, but the study was small, nonrandomized, and not dose matched.

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
McCormick R, Dawson B, Sim M, Lester L, Goodman C, Peeling P. 2020Eight-week prospective nonrandomized parallel-group comparison14No funding statement in the article (not established); no manufacturer-supply statement eitherFortnightly serum ferritin; exploratory hemoglobin mass and VO2max in the patch groupOral iron was 15.27 micrograms/L higher at week 6 (P=.019); no beneficial ferritin effect was found for the patchOnly direct human comparison, but nonrandomized and not dose matched
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Receipt — 1 References

All 1 cited sources were verified for existence at the original page (as of 2026-08-17).

McCormick R, Dawson B, Sim M, Lester L, Goodman C, Peeling P. The Effectiveness of Transdermal Iron Patches in Athletes With Suboptimal Iron Status (Part 1). Int J Sport Nutr Exerc Metab. 2020;30(3):185-190. PMID: 32217791. DOI: 10.1123/ijsnem.2019-0309.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-08-17 · Corrections: none

Cite this verdict

Transdermal iron patch x increased iron stores in athletes Evidence Grade D card
[Chamgap] Transdermal iron patch x increased iron stores in athletes — Evidence Grade D·28. 1 cited sources checked. Source: https://chamgap.com/en/verdicts/sports/transdermal-iron-patch-athlete-iron-stores/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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What this document does and does not do

Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.