Iron AbsorptionNCT07139821
Dietary Iron Requirements
A study testing Stable iron isotope in people with Iron Absorption, run by Pennington Biomedical Research Center at 2 sites in United States.
Trial summary
Dietary Reference Intakes (DRIs) for iron are based on a relatively small number of studies in European populations. This research study will determine iron needs in a representative sample of adults living in the US using the iron isotope dilution technique. Read more about this study
- Who is it for?
- Ages 18 to 50 yearsHealthy volunteers can take part
- Conditions the study is for
- Iron Absorption
- What is being tested?
- Stable iron isotope
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 300 participants
- Where
- 2 sitesUnited States
- Study dates
- 6 Feb 2026to 31 May 2029
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 50 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Males and premenopausal females age 18-50 y
- Previously participated in an iron stable isotope study or willing to consume an oral stable iron isotope and undergo a one-year equilibration period
- Willing to refrain from iron-containing supplements for the duration of the study
- Willing to refrain from tobacco smoking for the duration of the study
- Have not donated blood 3 months prior to the start of the study and willing to refrain from donating blood for the duration of the study
- Willing to have blood stored for future use
- Able and willing to comply with study requirements and consent to participate
Who cannot join
- Females: pregnant or lactating or plans to become pregnant during the study period
- Inability to provide informed consent and engage in informed consent procedures
- Plans to relocate outside the study area
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
United States2 sites, 2 recruiting
- Recruiting
LSU Pennington Biomedical Research Center
Baton Rouge, Louisiana, 70808
Stephen Hennigar, PhD, 225-763-2612, stephen.hennigar@pbrc.edu
- Recruiting
Cornell University
Ithaca, New York, 14853
Kimberly O'Brien, PhD, 607-255-3743, koo4@cornell.edu
About this study
Official title: Dietary Iron Requirements in US Adults
Dietary Reference Intakes (DRIs) for iron are based on a relatively small number of studies in European populations. This research study will determine iron needs in a representative sample of adults living in the US using the iron isotope dilution technique. Following administration and equilibration of a stable iron isotope, participants will be followed for a 12 week study period. Blood will be collected every 4 weeks and the isotopic composition will be determined. Results will help update dietary iron guidelines making sure they better match the specific needs of the US population.
- Conditions
- Iron Absorption
- Being tested
- Stable iron isotope
- Keywords
- Iron absorption, Iron losses, Iron requirements, Iron deficiency, Iron deficiency anemia, Iron isotopes
- Medical subject headings
- Iron Deficiencies, Anemia, Iron-Deficiency
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Stable iron isotopeOther
Stable iron isotopes will be used to determine iron requirements.
| Study group | Role | What they receive |
|---|---|---|
| US males and premenopausal females | Experimental | A representative sample of adult males and premenopausal females living in the US Receives: Other: Stable iron isotope |
What is being measured
The primary outcome is the main question the study is designed to answer.
Iron isotope composition in blood
Tracer-to-tracee rate in venous blood samples collected at multiple time points
Measured: 12 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Aug 2025
- Study start6 Feb 2026
- Primary completion1 Aug 2028 (estimated)
- Study completion31 May 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Iron AbsorptionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 300 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Pennington Biomedical Research Center
- Sponsor type
- University, hospital or other
- Collaborators
- Cornell University
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07139821
- Sponsor's protocol ID
- 2025-036-PBRC
- Status last verified
- Feb 2026
- First submitted
- 7 Aug 2025
- Last updated
- 29 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 29 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Dietary Iron Requirements in US Adults
- ClinicalTrials.gov ID
- NCT07139821
- Acronym / sponsor ID
- 2025-036-PBRC
- Conditions
- Iron Absorption
- Keywords
- Iron absorption, Iron losses, Iron requirements, Iron deficiency, Iron deficiency anemia, Iron isotopes
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 300 participants (estimated)
- Lead sponsor
- Pennington Biomedical Research CenterUniversity, hospital or other
- Collaborators
- Cornell University
- Study start
- 6 Feb 2026 (actual)
- Primary completion
- 1 Aug 2028 (estimated)
- Study completion
- 31 May 2029 (estimated)
- First posted
- 24 Aug 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Dietary Reference Intakes (DRIs) for iron are based on a relatively small number of studies in European populations. This research study will determine iron needs in a representative sample of adults living in the US using the iron isotope dilution technique. Following administration and equilibration of a stable iron isotope, participants will be followed for a 12 week study period. Blood will be collected every 4 weeks and the isotopic composition will be determined. Results will help update dietary iron guidelines making sure they better match the specific needs of the US population.
Study design
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| US males and premenopausal females | Experimental | Other: Stable iron isotopeA representative sample of adult males and premenopausal females living in the US |
Who may qualify
- Ages
- 18 to 50 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (7 listed)
- Males and premenopausal females age 18-50 y
- Previously participated in an iron stable isotope study or willing to consume an oral stable iron isotope and undergo a one-year equilibration period
- Willing to refrain from iron-containing supplements for the duration of the study
- Willing to refrain from tobacco smoking for the duration of the study
- Have not donated blood 3 months prior to the start of the study and willing to refrain from donating blood for the duration of the study
Key exclusion criteria (3 listed)
- Females: pregnant or lactating or plans to become pregnant during the study period
- Inability to provide informed consent and engage in informed consent procedures
- Plans to relocate outside the study area
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Stable iron isotopeStable iron isotopes will be used to determine iron requirements. | Other | US males and premenopausal females |
Primary outcome
Iron isotope composition in blood
Time frame: 12 weeks
Tracer-to-tracee rate in venous blood samples collected at multiple time points
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Apr 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Stable iron isotope in people with Iron Absorption, run by Pennington Biomedical Research Center at 2 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 29 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Stephen Hennigar, PhD (225-763-2612, stephen.hennigar@pbrc.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Iron isotope composition in blood (time frame: 12 weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Apr 2026.