Oral iron supplements and blood sugar response in overweight and obese women

The Effect of Oral Iron Supplements on Insulin and Glucose Metabolism in Overweight and Obese Women

This trial will test whether 14 days of daily low-dose versus high-dose oral iron changes insulin and blood sugar responses in overweight or obese women with low iron stores.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 70 (estimated)
• Ages: 18 Years to 45 Years
• Sex: Female
• Sponsor: ETH Zurich (Academic / other)
• Locations: 1 site (Beirut)
• Trial ID: NCT07315282 on ClinicalTrials.gov

What this trial studies

This is a randomized, double-blind metabolic intervention that will enroll 70 overweight or obese women with low ferritin and randomize them to 14 days of either low-dose (15 mg ferrous fumarate) or high-dose (195 mg ferrous sulfate) oral iron. Participants will have fasting blood draws and a standard oral glucose tolerance test (OGTT) with samples at 0, 1, and 2 hours at baseline (Day 0), after supplementation (Day 14), and four days after stopping iron (Day 17). Key exclusions include existing type 2 diabetes, recent high-dose iron or transfusion, smoking, or medical disorders affecting iron metabolism. The trial compares short-term changes in glucose and insulin dynamics between the two dosing groups.

Who should consider this trial

Good fit: Ideal candidates are non-smoking overweight or obese women (BMI ≥ 27.5 kg/m2) with low iron stores (serum ferritin <30 µg/L), hemoglobin ≥11 g/dL, fasting glucose <5.6 mmol/L, and no recent high-dose iron or transfusion.

Not a fit: Women with normal or high ferritin, existing type 2 diabetes, active smoking, recent iron therapy or transfusion, medical disorders that affect iron metabolism, men, and people unable to attend the Beirut visits are unlikely to benefit from participating.

Why it matters

Potential benefit: If successful, the results could clarify whether common iron supplements affect short-term glucose and insulin regulation and help guide iron therapy decisions for overweight women.

How similar studies have performed: Observational studies have linked higher iron stores to worse glucose metabolism and some trials of iron removal improved insulin sensitivity, but short-term randomized comparisons of oral iron doses in overweight women are limited.

Eligibility criteria

Inclusion Criteria:

* BMI ≥ 27.5 kg/m2
* serum ferritin \<30 μg/L
* hemoglobin ≥ 11 g/dl
* fasting blood glucose \< 5.6 mmol/L

Exclusion Criteria:

* intravenous or high dose oral iron in the preceding 2 months
* medical disorders are known to affect iron absorption or metabolism, or T2DM
* cigarette smoking
* recent blood transfusion or major blood loss

Where this trial is running

Beirut

• American University of Beirut — Beirut, Lebanon (Recruiting)

Study contacts

• Study coordinator: Omar Obeid

Conditions Overweight and Obese Women