Iron absorption and losses in young South African women with and without overweight or obesity

Long-term Iron Absorption and Losses in Young South African Women Living Without and With Overweight and Obesity

Not applicable Interventional North-West University, South Africa · NCT07081152

This study tests whether young South African women with overweight or obesity absorb and lose iron differently than women without overweight by giving a labeled iron drink and following them for a year.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment70 (estimated)
Ages18 Years to 35 Years
SexFemale
SponsorNorth-West University, South Africa Academic / other
Locations1 site (Potchefstroom, North West)
Trial IDNCT07081152 on ClinicalTrials.gov

What this trial studies

This longitudinal interventional study enrolls about 70 young women of African descent with either normal weight or overweight/obesity and low-to-moderate iron stores. In phase 1 participants receive a test drink containing 15 mg of 57Fe-labelled ferrous sulfate and fractional iron absorption is measured by incorporation of the isotope into red blood cells 14 days later. Participants then enter a one-year follow-up with monthly contacts to track health status, supplement use, blood donation, dietary iron intake, and iron and inflammation biomarkers. The study compares absorption and iron losses between the BMI groups and monitors changes in iron and inflammatory status over time.

Who should consider this trial

Good fit: Ideal candidates are young women of African descent with BMI in the study ranges (18.5–24.9 kg/m2 for the non-overweight group or ≥28 kg/m2 for the overweight/obesity group), low-to-moderate iron stores (ferritin ≤50 µg/L), the specified CRP profile, not anemic, and planning to remain in the study area for at least two years.

Not a fit: Women who are pregnant or lactating, have significant anemia (hemoglobin <11 g/dL), chronic inflammatory or malabsorptive disorders, take chronic anti-inflammatory medications, or otherwise meet exclusion criteria are unlikely to be eligible or to directly benefit from participation.

Why it matters

Potential benefit: If successful, the results could help tailor iron recommendations and interventions for young women with overweight or obesity to reduce the risk of iron deficiency.

How similar studies have performed: Previous studies have used stable isotopes to quantify iron absorption in normal-weight African women, but directly comparing long-term absorption and losses between women with and without overweight/obesity is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Of African descent
* BMI of 18.5 to 24.9 kg/m2 for participants living without OW/OB and BMI ≥ 28 kg/m2 for participants living with OW/OB
* Having low to moderate inflammation-adjusted iron stores (ferritin ≤50 µg/L)
* Absence of low-grade inflammation (CRP\<2 mg/l) for participants living without OW/OB and presence of low-grade inflammation CRP 2-20 mg/l) for participants living with OW/OB
* Planning to reside in the study area for at least 2 years

Exclusion Criteria:

* Hemoglobin \< 11 g/dl
* Treated or self-reported chronic or malabsorptive disorder
* Current use of chronic anti-inflammatory medication, like corticosteroids or non-steroidal anti-inflammatory medication
* Pregnancy or planning to become pregnant in the next 2 years
* Lactation
* Fear of needles or experiencing vaso-vagal episodes when exposed to blood
* Difficulty drawing blood due to poor quality veins
* Blood donation in the past 4 months or plans to donate blood during the study
* On a weight-loss diet or program or planning to start the same during the study
* Smoking
* Unwillingness to stop taking iron and /or vitamin C-containing supplements during phase 1 of the study
* Regular use of antacids, proton pump inhibitors or H2 blockers

Additional inclusion criteria applicable to phase 2 of the study

* Labelled with stable iron isotope (tracer) for a minimum of one year
* Willingness not to start or stop contraceptive use during the 6 months
* BMI ≥ 18.5 to 24.9 kg/m2 for participants living without OW/OB and BMI ≥ 28 kg/m2 for participants living with OW/OB

Additional exclusion criteria applicable to phase 2 of the study

\- Blood transfusion, intravenous iron infusion, blood donation or significant blood loss during the equilibration period

Where this trial is running

Potchefstroom, North West

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions ObesityIron DeficiencyInflammation
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.