Absorption of plant-derived heme iron

Iron Absorption From Plant-Derived Heme Iron: An Experimental Study in Iron-Deficient Women (PHIA)

We will test whether two plant-based heme iron compounds are absorbed as well as standard iron supplements in women with low iron stores.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 45 (estimated)
• Ages: 18 Years to 45 Years
• Sex: Female
• Sponsor: ETH Zurich (Academic / other)
• Locations: 1 site (Zurich)
• Trial ID: NCT07143890 on ClinicalTrials.gov

What this trial studies

This randomized, within-subject crossover trial gives iron-depleted but non-anemic women single meals containing one of four intrinsically stable isotope–labeled iron compounds (iron chlorophyllin, soy hemoglobin, ferrous sulfate as a negative control, and porcine hemoglobin as a positive control). Each participant consumes all test conditions in randomized order, with absorption measured 14 days after each test meal by erythrocyte incorporation of the stable iron isotopes. Absorption is tested in two matrices: water (no-matrix) and maize porridge (an inhibitory matrix) to see how dietary inhibitors affect uptake. The design allows direct within-person comparison of fractional iron absorption across compounds and matrices.

Who should consider this trial

Good fit: Adult women with low iron stores (serum ferritin <45 µg/L), normal BMI (18.5–24.9 kg/m2), body weight under 70 kg, not anemic, not pregnant or breastfeeding, and able to attend visits at ETH Zurich.

Not a fit: People who are anemic (Hb <120 g/L), have inflammation or chronic disease, recent significant blood loss/transfusion, strict vegans/vegetarians, or those using long-term supplements or medications are excluded and unlikely to benefit from participation.

Why it matters

Potential benefit: If successful, plant-derived heme iron could become a more effective iron fortificant that improves iron uptake while resisting common dietary inhibitors.

How similar studies have performed: Heme iron from animal sources is well documented to be highly bioavailable, but human data on plant-derived heme compounds are limited and this approach is relatively novel.

Eligibility criteria

Inclusion Criteria:

* Serum ferritin \< 45 µg/L (iron depleted)
* Body weight \< 70 kg
* Body mass index 18,5 - 24,9 kg/m2 (normal weight)

Exclusion Criteria:

* Hb \< 120 g/L (anemia)
* CRP \> 5 µg/L (inflammation)
* Strict vegan and vegetarians
* Any metabolic, gastrointestinal kidney or chronic disease
* Consumption of mineral and vitamin supplements since screening and over the study period until last blood sample collection
* Blood transfusion over the past 6 months
* blood donation over the past 6 months
* Significant blood loss (accident, surgery) over the past 6 months
* Women who are pregnant or breast feeding
* Smoker (\> 1 cigarette per week)
* Continuous/long-term use of medication (except for contraceptives)
* Therapeutic iron infusion over the past 6 months,
* Known hypersensitivity or allergy to iron supplements,
* Intention to become pregnant during the course of the studies,
* Known or suspected non-compliance, drug or alcohol abuse,
* Inability to follow the procedures of the studies, e.g. due to language problems, psychological disorders, dementia, etc. of the participant,
* Participation in another study with investigational drug within the 30 days preceding and during the present studies,
* Enrolment of the investigator, his/her family members, employees and other dependent persons

Where this trial is running

Zurich

• ETH Zurich, Laboratoy of Clinical Biopharmacy — Zurich, Switzerland (Recruiting)

Study contacts

• Study coordinator: Salome Häcki

Conditions Iron Deficiency; Iron Absorption; Iron sulfate; Iron fortification; plant-derived heme iron; Stable isotopes; Iron bioavailability