Iron Absorption From Plant Heme Iron

Summary

Heme, an iron protoporphyin IX complex, consists of a ferrous ion captured in a porphyrin ring acting as a tetradentate ligand. The unique features of heme iron -its unusually high absorption in foods and its resistance to luminal inhibitors of iron absorption- make it a potentially interesting iron fortificant. This study aims to compare fractional iron absorption from two plant-derived heme iron compounds-iron chlorophyllin and soy hemoglobin-with ferrous sulfate (negative control) and porcine hemoglobin (positive control) in iron-deficient women. All four compounds will be intrinsically labeled with stable iron isotopes. Fractional absorption will be assessed 14 days after test meal administration via erythrocyte iron incorporation.

Absorption will be tested in two matrices: water and maize porridge (an inhibitory matrix). Each participant will consume all test conditions in a randomized order, allowing for within-subject comparisons.

Conditions

• Iron Deficiency (ID)
• Iron Absorption

Interventions

OTHER

Iron chlorophyllin + no-matrix

Water with labelled Fe chlorophyllin (54Fe)

OTHER

SoyHb + no-matrix

Water with labelled soy hemoglobin (58Fe)

OTHER

FeSO4 + no-matrix

Water with labelled ferrous sulfate (58Fe)

OTHER

Hb + no-matrix

Water with labelled porcine hemoglobin (57Fe)

OTHER

Iron chlorophyllin + meal-matrix

Maize porridge with labelled Fe chlorophyllin (54Fe)

OTHER

SoyHb + meal-matrix

Maize porridge with labelled soy hemoglobin (58Fe)

OTHER

FeSO4 + meal-matrix

Maize porridge with labelled ferrous sulfate (57Fe)

OTHER

Hb + meal-matrix

Maize porridge with labelled porcine hemoglobin (57Fe)

Sponsors & Collaborators

• ETH Zurich

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

45 Years

Sex

FEMALE

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-09-22

Primary Completion

2026-05-31

Completion

2026-05-31

Countries

• Switzerland

Study Locations