Measuring Iron Bioavailability From Oral Iron Supplements in Healthy Pre-menopausal Women Using Stable Isotopes

What this trial studies

In this study the investigators will compare iron absorption from 3 doses of iron (5, 10, 15 mg, given as either Spatone™ or ferrous sulphate). Our primary objective is to determine iron absorption from each preparation by measuring stable isotope (57Fe) incorporation into haemoglobin.

Conditions in scope

• Iron Deficiency Anaemia Due to Dietary Causes

Interventions

• 5mg Spatone (Dietary Supplement) — 5mg Spatone
• 10mg Spatone (Dietary Supplement) — 10mg Spatone
• 15mg Spatone (Dietary Supplement) — 15mg Spatone
• 5mg ferrous sulphate (Dietary Supplement) — 5mg ferrous sulphate
• 10mg ferrous sulphate (Dietary Supplement) — 10 mg ferrous sulphate
• 15mg ferrous sulphate (Dietary Supplement) — 15mg ferrous sulphate

Who can join

Women only · Ages 19 Years to 49 Years · Accepts healthy volunteers.

Inclusion criteria

• Healthy pre-menopausal women
• Aged 19-49 years
• With low iron stores (below 30 μg/L serum ferritin; normal range 30-100 μg/L).

Exclusion criteria

• Allergy to iron supplements
• BMI above 25
• Pregnant
• Post-menopausal women
• History of alcohol or substance abuse
• Reported history of CVD, diabetes, cancer, kidney, liver or intestinal disease, gastrointestinal disorder
• Use of drugs likely to alter gastrointestinal function
• Donated blood recently (within the last 3 months prior to screening visit)

Eligibility wording paraphrased from the public record. View the full criteria on ClinicalTrials.gov before contacting a site.

Where it’s happening

Status & timeline

• Overall status: Completed
• Study type: Interventional
• Phase: N/A
• Start date: 2024-01-13
• Primary completion: 2025-03-31
• Last update posted: 2026-05-04
• First posted: 2026-05-04

Sponsor & contact

Lead sponsor: King's College London (Other)

For trial site contact information, use the official record at ClinicalTrials.gov. Contact details change frequently and the public record is the source of truth.

Outcome measures

Primary outcomes

• Iron Status Indicators (Day 1, Day 14, Day 28, Day 42, Day 56, Day 70, Day 84)
  The baseline blood sample, taken prior to the first intervention, will establish the participant's iron status before any treatment is administered. This includes, but is not limited to, serum ferritin, haemoglobin, and transferrin saturation. Post-Intervention Iron Status: Subsequent blood samples, taken two weeks after each intervention will be analysed to assess iron absorption from each supplemental iron preparation.

Related ClearedRx care

If you’re reading this trial because you have menopause symptoms now, you don’t have to wait for a trial to access evidence-based care. ClearedRx prescribes the same FDA-approved and compounded HRT products that have been studied in trials like this one for decades.