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Comparing 3 approaches for iron deficiency

Official title: Improving Iron Levels in Female Endurance, Intermittent, and Power/Strength Athletes Aged 16-35

Iron Revisited: Alternate-Day Oral Iron Supplementation in Endurance, Intermittent, and Power/Strength Athletes

Condition: Iron DeficiencySponsor: University of CalgaryTarget enrollment: 36
  • 3 groups
  • One site, in Calgary
  • Recruiting
University of Calgary, Calgary, Alberta

Interventions

  • Other intervention

    Low-dose iron (ferrous sulfate)

    Encapsulated low-dose ferrous sulphate (40mg elemental iron)

  • Other intervention

    Yeast-bound iron (ferrous sulfate)

    Encapsulated yeast-bound low-dose ferrous sulphate (40mg elemental iron)

  • Other intervention

    High-dose iron (ferrous sulfate)

    Encapsulated high-dose ferrous sulphate (150mg elemental iron)

Canadian Sites (1)

1 of 1 recruiting

  • University of Calgary

    Calgary, Alberta

    Recruiting

Eligibility Criteria

See who this study is looking for63 criteria

The trial’s own eligibility text, word for word from the registry. Only the trial site can say who takes part.

Inclusion

  • +Biologically female athlete
  • +At least one year past the age of menarche
  • +Complete and pass the Get Active Questionnaire (GAQ)
  • +Suboptimal ferritin levels (≤50 mcg/L)
  • +Provide informed consentInformed consentThe process of being told what taking part involves, then choosing freely.Read more → to participate in study
  • +Activity level based on Participant Classification Framework (McKay et al., 2022)
  • +Tier 3: Highly Trained / National Level
  • +Tier 4: Elite / International Level
  • +Energy availability \>30 kcal/kg LBM
  • +Have access to a smartphone, tablet, or computer
  • +Able to swallow a capsule sized 25mm length and 8mm width (i.e. large dose omega 3 pill)

Exclusion

  • Known allergy of hypersensitivity to any ingredient, including non-medicinal ingredients, such as iron, yeast, cellulose, or maltodextrin
  • Non-English speaking
  • Anemic (hemoglobin \<120g/L)
  • Regular prebiotic (fiber) or probiotic use within 4 weeks of study enrollmentEnrolmentThe number of participants a study plans to include, or has included.Read more →
  • Current laxative use
  • Consume \>21 units of alcohol per week
  • Have donated blood in the previous 3 months
  • Have a BMI \<16 but \>30kg/m2
  • Are dieting for weight loss or are following a low carbohydrate diet
  • Have participated in another clinical trialInterventional studyA study where participants are given something to see what happens.Read more → within the 30 days preceding study enrollment.
  • Are taking medications known to affect cardiovascular or metabolic responses to exercise such as beta-blockers, anti-coagulants etc. as assessed by the Principal InvestigatorPrincipal investigatorThe doctor or researcher responsible for running the study at a site.Read more →
  • Known history of thalassemia or thalassemia trait
  • Known inherited bleeding disorder
  • Chronic use of Salicylates, aspirin, corticosteroids, or nonsteroidal anti-inflammatory drugs
  • Have any of the following conditions: renal or gastrointestinal disorders, autoimmune disease, metabolic disease, heart disease, vascular disease, rheumatoid arthritis, diabetes, poor lung function, uncontrolled blood pressure, dizziness, thyroid problems, or any other health conditions that are being treated and deemed to be able to significantly interfere with study intervention and assessment in the opinion of the Principal Investigator and Qualified Investigator
  • Have current musculoskeletal injuries that limit exercise capacity
  • Self-identifying with any kidney or gastrointestinal issues, metabolic disorders, cardiac conditions, vascular illnesses, rheumatoid arthritis, diabetes, compromised lung function, unregulated blood pressure, episodes of dizziness, thyroid complications, or any other health conditions under treatment that might potentially interfere with the study results
  • Orthopaedic issues that limit exercise ability
  • Currently/last 3 months taking prescription medications that are known to affect iron absorption (i.e. Antacids/PPIs (e.g., omeprazole), H2 Blockers (e.g., ranitidine), Tetracycline Antibiotics (e.g., doxycycline), Quinolone Antibiotics (e.g., ciprofloxacin), Cholestyramine, Colchicine, Methyldopa.)
  • Currently taking levodopa or levothyroxine
  • Currently/last 3 months taking iron containing supplements
  • Barrier methods (e.g. condoms with spermicide, diaphragms with spermicide)
  • Intrauterine devices
  • Vasectomy of partner at least 6 months prior to screeningScreeningThe checks done before joining, to see whether a study fits.Read more →
  • Additional exclusion criteriaExclusion criteriaThe things that would prevent someone from taking part.Read more → based on use of SIMBA capsules. Following is a summary of SIMBA capsules specific exclusion criteria:
  • History of known structural gastrointestinal abnormalities such as structures or fistulas leading to mechanical obstruction
  • Have any gastrointestinal inflammatory diseases, including ulcerative colitis, Crohn's disease, microscopic colitis.
  • Use of any medication in the week prior to the screening study visit, unless part of regular treatment, that could substantially alter gastrointestinal motor function (e.g. opioids, prokinetics, anticholinergics, GLP-1 analogues); laxative use is allowed if it is kept unchanged in the week prior to the study visit. Proton pump inhibitors (PPIs) are allowed provided a wash-outWashout periodA gap with no treatment, so the previous one clears your system.Read more → period of 48 hours is respected before swallowing the SIMBA capsules and PPI treatment is resumed only 4 hours thereafter.
  • Prokinetic (stimulate muscle contractions, Metoclopramide, Domperidone, Prucalopride, etc.) use. If you are not using prokinetics to treat SIBO, then you may be eligible after a 2-week washout period, and willing to not use prokinetics for the study duration.
  • Unable to stop using laxatives or prokinetic medications for 4 days before the study procedure (breath test). Laxatives can be resumed after the test is conducted.
  • Have used antibiotics (except for topical use) in the previous 12 weeks. You may be eligible to participate once a 12-week washout is completed
  • Regular use of probiotics, prebiotics, or synbiotics (including food and drinks containing added probiotics and/or probiotic yogurts with live, active cultures)
  • Have digestive problems that slow or stop food from moving properly, like a slow stomach, blocked intestines, or stiffened tissues
  • Suffer from celiac disease (treated or untreated)
  • Organic motility disorder, including gastroparesis, intestinal pseudo-obstruction, systemic sclerosis, Ogilvie's syndrome
  • History of oropharyngeal dysphagia, or other swallowing disorder with a risk of capsule aspiration
  • Have had a cancer diagnosis or treatment within the past year (non-melanoma skin cancers are acceptable)
  • Have trouble swallowing, which could cause a risk of choking on a capsule
  • Participants scheduled for an MRI at any time during the study. You may be eligible to participate once your MRI procedure is completed.
  • Have constant constipation (IBS-C) defined as a history of less than 3 bowel movements per week
  • Any prior fecal microbiota transplantation
  • Suffer from alcohol or drug abuse
  • Are pregnant or lactating or planning to become pregnant for the duration of the study. All participants must agree to use a medically approved method of birth controlControl groupThe group a new treatment is measured against.Read more → for the duration of the study. All hormonal birth control must have been in use for a minimum of three months. Acceptable methods of birth control include:
  • Abstinence or agrees to use contraception if planning to become sexually active
  • Hormonal contraceptives including oral contraceptives, hormone birth control patch
  • Vaginal contraceptive ring, injectable contraceptives, or hormone implant
  • Non-heterosexual lifestyle or agrees to use contraception if planning on changing to heterosexual partner(s)
  • Currently pregnant, planning to become pregnant, or breastfeeding
  • Females of childbearing potential will be asked about their likelihood of being pregnant, based on factors such as recent sexual activity or use of contraception. Their self-reported confirmation of non-pregnancy will be accepted unless they express uncertainty. In cases of doubt, a urine beta-HCG pregnancy test will be required for confirmation. If you become pregnant during the course of the study, you should stop taking the supplement immediately and inform the investigators. If you are using a supplement that the investigators have deemed to not interfere with the study's intervention or assessment (e.g. vitamins, omega-3, creatine monohydrate etc.), you will be permitted to continue taking these supplements. In all cases, participants will be instructed to not change the dose of the taken supplement or introduce a new supplement unless it is medically recommended.
  • Major surgery in the past 3 months
  • Prior gastrointestinal disease, surgery, or radiation treatment which, in the Investigator's opinion, would lead to intestinal structuring, narrowing, or obstruction with a risk of capsule non-excretion, including, e.g. achalasia, eosinophilic esophagitis, any IBD, or previous esophageal, gastric, small intestinal, or colonic surgery. Appendectomy or cholecystectomy more than 3 months before the screening visit is acceptable.
  • Are a smoker or use tobacco products
5 concepts to explore on this page · up to 1,300 pointsTap any term to learn what it means.

In plain language

Assembled directly from this trial’s registry record. Every sentence traces to a field below — nothing here is generated or interpreted.

Learning 
What this study is

This study is testing a treatment for a condition.

This study is not organised into the usual phase numbers — that is common for device, behavioural, and diagnostic research.

From the trial registry

Built from these fields:

  • designModule.designInfo.primaryPurpose
  • designModule.phases
Who receives what

There are 3 groups in this study.

Group A, the comparison group, receives Low-dose iron (ferrous sulfate).

Registry label: A: Low dose iron supplement

Group B receives Yeast-bound iron (ferrous sulfate).

Registry label: B: Low dose iron supplement bound to yeast

Group C, the comparison group, receives High-dose iron (ferrous sulfate).

Registry label: C: High dose iron supplement

From the trial registry

Built from these fields:

  • armsInterventionsModule.armGroups[].label
  • armsInterventionsModule.armGroups[].type
  • armsInterventionsModule.armGroups[].interventionNames
How the study is run

Which group you would be placed in is decided by chance, like a coin flip — not by you and not by your doctor.

You, the study team, the people giving the treatment, and the people analysing the results would all be kept unaware of which group you are in until the study ends.

From the trial registry

Built from these fields:

  • designModule.designInfo.allocation
  • designModule.designInfo.maskingInfo.masking
Is there a placebo?

This study does not list a placeboPlaceboA dummy treatment with no active medicine, used for comparison.Read more → group.

One group receives an existing treatment, so the two can be compared.

From the trial registry

Built from these fields:

  • armsInterventionsModule.armGroups[].type
  • armsInterventionsModule.armGroups[].interventionNames
Who the study is looking for

The study lists an age range of 16 years to 35 years.

The study lists female participants only.

The study accepts healthy volunteersHealthy volunteerSomeone without the condition being studied who takes part anyway.Read more → as well as people with the condition.

These are the criteria the study lists. Only the trial siteTrial siteA hospital or clinic where a study is actually run.Read more → can decide whether someone can take part.

From the trial registry

Built from these fields:

  • eligibilityModule.minimumAge
  • eligibilityModule.maximumAge
  • eligibilityModule.sex
  • eligibilityModule.healthyVolunteers
How big and how long

The study aims to enrol about 36 people.

The study is currently expected to finish around September 2026.

The main measurement is taken over: BaselineBaselineYour starting measurements, taken before treatment begins.Read more →.

From the trial registry

Built from these fields:

  • designModule.enrollmentInfo.count
  • statusModule.completionDateStruct.date
  • outcomesModule.primaryOutcomes[].timeFrame
What the study measures

Iron status blood markers — measured over BaselineBaselineYour starting measurements, taken before treatment begins.Read more →.

Iron status blood markers — measured over 4 weeks.

Iron status blood markers — measured over 8 weeks.

Iron status blood markers — measured over 12 weeks.

The study lists 2 further main measurements.

From the trial registry

Built from these fields:

  • outcomesModule.primaryOutcomes[].measure
  • outcomesModule.primaryOutcomes[].timeFrame

Source: NCT06942208 on ClinicalTrials.gov. The full registry text is further down this page — this summary never replaces it.

Not medical advice. What do these terms mean?

What is being tested — in plain terms

About Low-dose iron (ferrous sulfate)Dietary supplement

Encapsulated low-dose ferrous sulphate (40mg elemental iron)

From the trial registry — its own words, unedited.

What a dietary supplement is here: A vitamin, mineral, or other supplement being studied.

Read the full explanation → · in clinical review

About Yeast-bound iron (ferrous sulfate)Dietary supplement

Encapsulated yeast-bound low-dose ferrous sulphate (40mg elemental iron)

From the trial registry — its own words, unedited.

What a dietary supplement is here: A vitamin, mineral, or other supplement being studied.

Read the full explanation → · in clinical review

About High-dose iron (ferrous sulfate)Dietary supplement

Encapsulated high-dose ferrous sulphate (150mg elemental iron)

From the trial registry — its own words, unedited.

What a dietary supplement is here: A vitamin, mineral, or other supplement being studied.

Read the full explanation → · in clinical review

Common questions

Answered from this trial’s registry record. Where the record doesn’t say, these answers say so rather than filling the gap.

Am I eligible for this trial?

Only the trial siteTrial siteA hospital or clinic where a study is actually run.Read more → can decide whether someone can take part. Concord cannot make that determination, and neither can any tool that has not examined you.

What the study lists: an age range of 16 years to 35 years.

The full inclusionInclusion criteriaThe things you must have or be for a study to consider you.Read more → and exclusion criteriaExclusion criteriaThe things that would prevent someone from taking part.Read more → are published on this page, exactly as the study team wrote them.

The useful next step is to bring this trial to your doctor. Answering a few questions first gives them something concrete to review.

From the trial registry
  • eligibilityModule.minimumAge
  • eligibilityModule.maximumAge
  • eligibilityModule.eligibilityCriteria
Is there a placebo?

This study does not list a placeboPlaceboA dummy treatment with no active medicine, used for comparison.Read more → group.

One group receives an existing treatment so the two can be compared.

From the trial registry
  • armsInterventionsModule.armGroups[].type
Would I know which treatment I am getting?

You, the study team, the people giving the treatment, and the people analysing the results would all be kept unaware of which group you are in until the study ends.

Which group you would be placed in is decided by chance, like a coin flip — not by you and not by your doctor.

From the trial registry
  • designModule.designInfo.maskingInfo.masking
  • designModule.designInfo.allocation
Who can join?

The study lists an age range of 16 years to 35 years.

It lists female participants only.

It accepts healthy volunteersHealthy volunteerSomeone without the condition being studied who takes part anyway.Read more → as well as people with the condition.

Only the trial siteTrial siteA hospital or clinic where a study is actually run.Read more → can confirm whether a particular person can take part.

From the trial registry
  • eligibilityModule.minimumAge
  • eligibilityModule.maximumAge
  • eligibilityModule.sex
  • eligibilityModule.healthyVolunteers
How long would this take?

The study's main measurement is taken over: BaselineBaselineYour starting measurements, taken before treatment begins.Read more →.

The study as a whole is currently expected to finish around 2026-09.

How long any one person takes part can differ from the study length. The study team can tell you what the schedule looks like in practice.

From the trial registry
  • outcomesModule.primaryOutcomes[].timeFrame
  • statusModule.completionDateStruct.date
How many people are taking part?

The study aims to enrol about 36 people.

From the trial registry
  • designModule.enrollmentInfo.count
Where is this happening?

This study lists one location: Calgary, Alberta, Canada.

Sites can open and close during a study, so confirm with the team before travelling.

From the trial registry
  • trial_locations

About This Trial

The goal of this clinical trial is to learn if different types and doses of oral iron supplements can improve iron levels, athletic performance, and gut health in young female athletes with low iron stores. The main questions it aims to answer are: * Does a low dose of yeast-bound iron improve iron status better than traditional iron supplements? * Do the different iron supplements cause fewer or more gastrointestinal (stomach) symptoms? * How do iron supplements affect exercise performance and gut bacteria? Researchers will compare three types of iron supplements: * A low-dose iron supplement (40 mg) * A low-dose yeast-bound iron supplement (40 mg) * A high-dose iron supplement (150 mg) This will help researchers find out which type of supplement is most effective and easiest on the stomach. Participants will: * Take one of the three assigned iron supplements every other day for 12 weeks * Complete fitness tests before and after the study, including cycling and jumping tests * Give blood samples to measure iron levels * Provide stool and intestinal samples to study gut bacteria * Swallow a SIMBA capsule before and after the study to collect a sample from the small intestine * Complete regular online surveys about sleep, stress, menstrual cycles, and gut symptoms

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This page is for informational purposes only and does not constitute medical advice. Clinical trial eligibility can only be determined by the trial site after proper screening. Trial information is sourced from ClinicalTrials.gov and may not reflect the most current status. Always consult your healthcare provider before making decisions about clinical trial participation.