Mechanism and regulation of iron absorption throughout the life cycle.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing mechanistic and physiological literature without systematic methodology.
PubMed 39814221 · doi:10.1016/j.jare.2025.01.002
What was done
This narrative review synthesizes recent literature on the molecular mechanisms and regulation of iron absorption across mammalian life stages. It evaluates iron transport pathways—primarily divalent metal-ion transporter 1 (DMT1) and ferroportin (FPN)—and systemic regulators such as hepcidin across fetal, infant, adult, and elderly stages.
What was found
The abstract reports no numerical data. Mechanistically, it notes that fetal iron uptake occurs across the placenta and is regulated by maternal stores; infants may use alternative, non-DMT1/FPN pathways to support high demand; adults adjust absorption inversely to iron status via cellular and hepcidin-mediated pathways; and elderly individuals face altered hepcidin production linked to age-associated inflammation, hormonal alterations, and chronic disease.
Why it matters
Understanding stage-specific variations in iron regulation helps explain differing vulnerabilities to iron deficiency or overload across the lifespan and may guide age-specific therapeutic targets.
Limits
The paper is a narrative review without systematic search protocols, meta-analytic pooling, or quantitative effect sizes. Hypothesized mechanisms such as alternative infant iron absorption routes require validation in human clinical trials.
Cited by
- supports The human body has difficulty excreting or eliminating excess iron.
- supports The human body lacks an active physiological mechanism to excrete excess iron.