Non-Anemic Iron DeficiencyNAID-FNCT07263529
Risk of Anemia and Effects of Oral Iron Therapy in Non-Anemic Iron-Deficient Women (18-55 Years)
A study testing Dietary Intervention (2 months) and Oral Elemental Iron (Ferrous Sulfate) 80 mg/day in people with Non-Anemic Iron Deficiency, run by Istanbul University - Cerrahpasa at 1 site in Turkey (Türkiye).
Trial summary
This study investigates the risk of anemia development in women aged 18-55 years with non-anemic iron deficiency and evaluates the clinical effects of oral iron therapy. The study consists of a two-month nutritional intervention phase followed by a one-month oral iron treatment phase. Read more about this study
- Who is it for?
- Ages 18 to 55 years, women only
- Conditions the study is for
- Non-Anemic Iron Deficiency
- What is being tested?
- Dietary Intervention (2 months) and Oral Elemental Iron (Ferrous Sulfate) 80 mg/day
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 1 Sep 2025to 28 Feb 2026
- 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 55 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- Female participants aged 18-55 years (including premenopausal and menopausal women).
- Normal hemoglobin level (≥ 12 g/dL).
- Serum ferritin < 15 μg/L (WHO criteria for iron deficiency).
- Mentzer index > 13.
- Normal levels of vitamin B12, folic acid, thyroid hormones (TSH and sT4), and C-reactive protein (CRP < 5 mg/L).
- Non-anemic iron deficiency confirmed by laboratory results.
- Good general health and cognitive capacity to provide informed consent.
- Willingness to participate, comply with study procedures, and provide written informed consent.
Who cannot join
- Pregnancy or postpartum period.
- Acute or chronic infections.
- History or suspicion of malignancy.
- Chronic inflammatory or autoimmune diseases.
- Chronic fatigue syndrome or depressive disorders.
- Chronic kidney disease or renal failure (acute or chronic).
Show all 12Show fewer
- Congestive heart failure, ischemic heart disease, or cerebrovascular disease.
- Coagulopathy or clinically significant bleeding tendency.
- Hematological disorders (e.g., thalassemia, hemoglobinopathies).
- Postoperative patients, transplant recipients, or dialysis patients.
- Currently using any form of iron supplementation or treatment.
- Any condition that, in the investigator's opinion, may interfere with the participant's safety or the interpretation of study results.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)1 site, 1 recruiting
- Recruiting
Kagıthane No. 5 Family Health Center
Kâğıthane, Istanbul, 34413
Osman Demir, MD, +90 532 291 4470, osman.demir@iuc.edu.tr
Ayşen Fenercioğlu, Assoc Prof, +90 537 964 5751, aysen.fenercioglu@iuc.edu.tr
About this study
Official title: Risk of Anemia Development and Clinical Effects of Oral Iron Therapy in Women (18-55 Years) With Non-Anemic Iron Deficiency
This study investigates the risk of anemia development in women aged 18-55 years with non-anemic iron deficiency and evaluates the clinical effects of oral iron therapy. The study consists of a two-month nutritional intervention phase followed by a one-month oral iron treatment phase. Participants first receive dietary counseling aimed at increasing iron intake and absorption. After two months, changes in hematologic parameters and symptoms are evaluated. Women with persistent iron deficiency then receive daily oral ferrous sulfate (80 mg elemental iron) for one month. The study aims to identify early predictors of anemia progression and to assess the impact of dietary modification and oral iron therapy on symptoms and laboratory findings.
Read the detailed description
This study examines the risk of anemia development in women aged 18-55 years with non-anemic iron deficiency (NAID) and evaluates the clinical effects of oral iron therapy in those with persistent deficiency. The objective is to characterize individual and clinical factors associated with progression toward anemia and to assess the impact of nutritional modification and subsequent iron supplementation on hematologic and symptom-based outcomes.
Iron deficiency is one of the most common nutritional deficiencies globally. NAID often remains unrecognized despite its potential to cause fatigue, decreased physical performance, and progression to anemia if untreated. Iron plays a key role in oxygen transport, DNA synthesis, and muscle metabolism. Dietary intake includes both heme (animal-derived) and non-heme (plant-derived) forms with differing bioavailability. Ferritin is the primary biomarker used to diagnose iron deficiency, though inflammatory conditions may influence its accuracy. A careful differential evaluation is important to distinguish NAID from other causes of anemia such as chronic disease, B12 or folate deficiency, thalassemia syndromes, thyroid disorders, or gastrointestinal blood loss.
The study uses a two-phase, single-center prospective design at Kağıthane 5 No'lu Family Health Center (ASM), Istanbul, Turkey, conducted under ethics committee approval and institutional permission. In the initial two-month observational phase, participants receive standardized dietary counseling aimed at increasing iron intake and improving absorption. Health status and adherence are monitored biweekly. After this period, participants are categorized into four groups according to hematologic changes: isolated iron deficiency; microcytosis/hypochromia with minimal hemoglobin decline (<1 g/dL) ; greater hemoglobin decline without meeting anemia thresholds; or overt iron deficiency anemia.
In the subsequent one-month experimental phase, participants with persistent deficiency receive oral ferrous sulfate providing 80 mg elemental iron daily. Clinical and laboratory evaluations are performed at designated time points to assess changes in complete blood count parameters, ferritin, serum iron indices, inflammatory markers, and patient-reported symptoms.
Primary outcomes include changes in symptom scores, while secondary outcomes evaluate hematologic and biochemical responses. Planned analyses explore associations between baseline characteristics, dietary habits, and anemia progression. Power analysis using repeated measures ANOVA indicated a required sample size of 60 participants.
This research highlights the importance of individualized management strategies for iron deficiency, aiming to support appropriate use of supplementation while reducing unnecessary treatment and potential adverse effects. Enhancing dietary iron intake may help prevent anemia progression, promote patient safety, and improve resource utilization in primary care settings.
- Conditions
- Non-Anemic Iron Deficiency
- Being tested
- Dietary Intervention (2 months), Oral Elemental Iron (Ferrous Sulfate) 80 mg/day
- Keywords
- Iron deficiency without anemia, Risk of anemia, Clinical effects of oral iron therapy, Women 18-55, Ferritin, Hemoglobin, Symptom scores, Nutritional intervention, Iron supplementation
- Medical subject headings
- Iron Deficiencies
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Dietary Intervention (2 months)Other
Also called Nutritional Intervention (2 months)
A two-month nutritional counseling program for all participants (N = 60) with isolated non-anemic iron deficiency. The program emphasized the inclusion of iron-rich foods (both heme and non-heme sources), the use of enhancers of iron absorption (such as vitamin C), and practical strategies to reduce absorption inhibitors (e.g., limiting tea and coffee consumption around meals, reviewing antacid use). Participants received biweekly phone follow-ups to monitor adherence and assess symptoms.
Oral Elemental Iron (Ferrous Sulfate) 80 mg/dayDrug
Also called Oral Iron Intervention (1 month)
One-month oral therapy with 80 mg elemental iron (ferrous sulfate) daily for participants with persistent iron deficiency after the nutritional phase (ferritin < 15 µg/L). Biweekly phone follow-up for adherence and symptom checks. Adherence and side effects monitored at clinic visit or by phone.
| Study group | Role | What they receive |
|---|---|---|
| ARM 1 - Nutritional Intervention with Post-Intervention Subgrouping | Experimental | All participants (N=60) begin with isolated non-anemic iron deficiency and receive a 2-month standardized nutritional intervention to improve iron intake and absorption. Afterward, participants are stratified into five subgroups (ARM1-0 to ARM1-4) based on hematologic response. Subgroups ARM1-1 to ARM1-4 represent persistent deficiency (ferritin <15 µg/L with normal CRP) and will receive oral elemental iron.
* ARM1-0: Normalized or maintained iron status (no deficiency) - no iron therapy administered.
* ARM1-1: Persistent isolated iron deficiency - receives oral elemental iron.
* ARM1-2: Minimal hemoglobin decline (<1 g/dL) with microcytosis/hypochromia - receives oral elemental iron.
* ARM1-3: Hemoglobin decline >1 g/dL but above anemia threshold, with microcytosis/hypochromia - receives oral elemental iron.
* ARM1-4: Overt iron deficiency anemia - receives oral elemental iron. Receives: Other: Dietary Intervention (2 months); Drug: Oral Elemental Iron (Ferrous Sulfate) 80 mg/day |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change from Baseline in Patient-Reported Iron Deficiency Symptom Scores After 2-Month Nutritional Intervention and 1-Month Oral Iron Therapy
Change in patient-reported symptoms including fatigue, weakness, dizziness, and cognitive function etc. measured at baseline, after 2-month nutritional intervention, and after 1-month oral iron therapy.
Measured: Baseline, Week 8 (post-nutritional intervention), Week 12 (post-oral iron therapy)
Secondary outcomes (5)
Change from Baseline in Hemoglobin and Red Blood Cell Indices After 2-Month Nutritional Intervention and 1-Month Oral Iron Therapy
Hemoglobin, hematocrit, MCV, MCH, MCHC, and ferritin measured at baseline, Week 8, and Week 12.
Measured: Baseline, Week 8, Week 12
Change from Baseline in Serum Iron and Total Iron Binding Capacity After 2-Month Nutritional Intervention and 1-Month Oral Iron Therapy
Serum iron, TIBC, and ferritin measured at baseline, Week 8, and Week 12.
Measured: Baseline, Week 8, Week 12
Incidence of Progression to Anemia After 2-Month Nutritional Intervention
Number and proportion of participants who progress from non-anemic iron deficiency (baseline Hb ≥12 g/dL) to anemia (Hb <12 g/dL) measured at Week 8 (post-nutritional intervention). This outcome assesses the short-term risk of anemia development despite dietary counseling focused on iron-rich foods and absorption enhancement.
Measured: Baseline to Week 8
Proportion of Participants Demonstrating Hematologic Response to 1-Month Oral Iron Therapy (Hb increase ≥1.0 g/dL)
Proportion of participants with an increase in hemoglobin ≥1.0 g/dL between Week 8 (pre-treatment) and Week 12 (post-treatment). Hematologic response defined as hemoglobin increase ≥1.0 g/dL after 1-month oral ferrous sulfate (80 mg/day elemental iron) therapy.
Measured: Week 8 to Week 12
Proportion of Participants Demonstrating Ferritin Response to 1-Month Oral Iron Therapy (Ferritin increase ≥15 µg/L or ≥30 µg/L absolute)
Proportion of participants with ferritin increase ≥15 µg/L from Week 8 to Week 12, or achieving ferritin ≥30 µg/L at Week 12. Biochemical response reflecting iron store replenishment after oral iron therapy, measured by increase in serum ferritin.
Measured: Week 8 to Week 12
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Dec 2025
- Study start1 Sep 2025
- Primary completion1 Jan 2026 (estimated)
- Study completion28 Feb 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (17)Papers the sponsor has linked to this study.
- Other trials for Non-Anemic Iron DeficiencyStudies of the same condition, open and under way.
- More trials run by Istanbul University - CerrahpasaThe sponsor's other registered studies.
- 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
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- All participants initially receive the same nutritional intervention; after post-intervention evaluation, subgroups are defined and those with persistent iron deficiency receive the drug intervention.
- Masking
- None (open label)
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Istanbul University - Cerrahpasa
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Osman Demir, MD, Istanbul University - Cerrahpasa
- Investigators
- Osman Demir, MD, Principal investigator, Kağıthane No.5 Family Health Center, Istanbul, TurkeyAyşen Fenercioğlu, Assoc Prof, Study director, Istanbul University - Cerrahpaşa, Cerrahpaşa Faculty of Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07263529
- Sponsor's protocol ID
- 2024-KAEK-22
- Other IDs
- E-14028348-302.14.02-985103, E-15916306-604.01-281470566
- Acronym
- NAID-F
- Status last verified
- Nov 2025
- First submitted
- 16 Nov 2025
- Last updated
- 4 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Ortancil O, Sanli A, Eryuksel R, Basaran A, Ankarali H. Association between serum ferritin level and fibromyalgia syndrome. Eur J Clin Nutr. 2010 Mar;64(3):308-12. doi: 10.1038/ejcn.2009.149. Epub 2010 Jan 20.
PubMed 20087382Skolmowska D, Glabska D, Kolota A, Guzek D. Effectiveness of Dietary Interventions to Treat Iron-Deficiency Anemia in Women: A Systematic Review of Randomized Controlled Trials. Nutrients. 2022 Jun 30;14(13):2724. doi: 10.3390/nu14132724.
PubMed 35807904Silva Neto LGR, Santos Neto JED, Bueno NB, de Oliveira SL, Ataide TDR. Effects of iron supplementation versus dietary iron on the nutritional iron status: Systematic review with meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr. 2019;59(16):2553-2561. doi: 10.1080/10408398.2018.1459469. Epub 2018 Apr 30.
PubMed 29611716Moretti D, Goede JS, Zeder C, Jiskra M, Chatzinakou V, Tjalsma H, Melse-Boonstra A, Brittenham G, Swinkels DW, Zimmermann MB. Oral iron supplements increase hepcidin and decrease iron absorption from daily or twice-daily doses in iron-depleted young women. Blood. 2015 Oct 22;126(17):1981-9. doi: 10.1182/blood-2015-05-642223. Epub 2015 Aug 19.
PubMed 26289639Stefan MW, Gundermann DM, Sharp MH, Jennings BA, Gheith RH, Lowery RP, LowDog T, Ghatak SB, Barbosa J, Wilson JM. Assessment of the Efficacy of a Low-Dose Iron Supplement in Restoring Iron Levels to Normal Range among Healthy Premenopausal Women with Iron Deficiency without Anemia. Nutrients. 2023 Jun 3;15(11):2620. doi: 10.3390/nu15112620.
PubMed 37299583Nemeth E, Ganz T. Hepcidin and Iron in Health and Disease. Annu Rev Med. 2023 Jan 27;74:261-277. doi: 10.1146/annurev-med-043021-032816. Epub 2022 Jul 29.
PubMed 35905974Zhu XY, Wu TT, Wang HM, Li X, Ni LY, Chen TJ, Qiu MY, Shen J, Liu T, Ondo WG, Wu YC. Correlates of Nonanemic Iron Deficiency in Restless Legs Syndrome. Front Neurol. 2020 Apr 30;11:298. doi: 10.3389/fneur.2020.00298. eCollection 2020.
PubMed 32425874Sawada T, Konomi A, Yokoi K. Iron deficiency without anemia is associated with anger and fatigue in young Japanese women. Biol Trace Elem Res. 2014 Jun;159(1-3):22-31. doi: 10.1007/s12011-014-9963-1. Epub 2014 Apr 23.
PubMed 24756645da Silva Lopes K, Yamaji N, Rahman MO, Suto M, Takemoto Y, Garcia-Casal MN, Ota E. Nutrition-specific interventions for preventing and controlling anaemia throughout the life cycle: an overview of systematic reviews. Cochrane Database Syst Rev. 2021 Sep 26;9(9):CD013092. doi: 10.1002/14651858.CD013092.pub2.
PubMed 34564844Miles LF, Litton E, Imberger G, Story D. Intravenous iron therapy for non-anaemic, iron-deficient adults. Cochrane Database Syst Rev. 2019 Dec 20;12(12):CD013084. doi: 10.1002/14651858.CD013084.pub2.
PubMed 31860749Houston BL, Hurrie D, Graham J, Perija B, Rimmer E, Rabbani R, Bernstein CN, Turgeon AF, Fergusson DA, Houston DS, Abou-Setta AM, Zarychanski R. Efficacy of iron supplementation on fatigue and physical capacity in non-anaemic iron-deficient adults: a systematic review of randomised controlled trials. BMJ Open. 2018 Apr 5;8(4):e019240. doi: 10.1136/bmjopen-2017-019240.
PubMed 29626044Fletcher A, Forbes A, Svenson N, Wayne Thomas D; A British Society for Haematology Good Practice Paper. Guideline for the laboratory diagnosis of iron deficiency in adults (excluding pregnancy) and children. Br J Haematol. 2022 Feb;196(3):523-529. doi: 10.1111/bjh.17900. Epub 2021 Oct 24. No abstract available.
PubMed 34693519Clenin GE. The treatment of iron deficiency without anaemia (in otherwise healthy persons). Swiss Med Wkly. 2017 Jun 14;147:w14434. doi: 10.4414/smw.2017.14434. eCollection 2017.
PubMed 28634965WHO guideline on use of ferritin concentrations to assess iron status in individuals and populations [Internet]. Geneva: World Health Organization; 2020. Available from http://www.ncbi.nlm.nih.gov/books/NBK569880/
PubMed 33909381Balendran S, Forsyth C. Non-anaemic iron deficiency. Aust Prescr. 2021 Dec;44(6):193-196. doi: 10.18773/austprescr.2021.052. Epub 2021 Dec 1.
PubMed 35002031
Study at a glance
From the registry record, last updated by the sponsor on 4 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Risk of Anemia Development and Clinical Effects of Oral Iron Therapy in Women (18-55 Years) With Non-Anemic Iron Deficiency
- ClinicalTrials.gov ID
- NCT07263529
- Acronym / sponsor ID
- NAID-F / 2024-KAEK-22
- Conditions
- Non-Anemic Iron Deficiency
- Keywords
- Iron deficiency without anemia, Risk of anemia, Clinical effects of oral iron therapy, Women 18-55, Ferritin, Hemoglobin, Symptom scores, Nutritional intervention
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- Istanbul University - CerrahpasaUniversity, hospital or other
- Study start
- 1 Sep 2025 (actual)
- Primary completion
- 1 Jan 2026 (estimated)
- Study completion
- 28 Feb 2026 (estimated)
- First posted
- 4 Dec 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.
This study investigates the risk of anemia development in women aged 18-55 years with non-anemic iron deficiency and evaluates the clinical effects of oral iron therapy. The study consists of a two-month nutritional intervention phase followed by a one-month oral iron treatment phase. Participants first receive dietary counseling aimed at increasing iron intake and absorption. After two months, changes in hematologic parameters and symptoms are evaluated. Women with persistent iron deficiency then receive daily oral ferrous sulfate (80 mg elemental iron) for one month. The study aims to identify early predictors of anemia progression and to assess the impact of dietary modification and oral iron therapy on symptoms and laboratory findings.
Detailed description
This study examines the risk of anemia development in women aged 18-55 years with non-anemic iron deficiency (NAID) and evaluates the clinical effects of oral iron therapy in those with persistent deficiency. The objective is to characterize individual and clinical factors associated with progression toward anemia and to assess the impact of nutritional modification and subsequent iron supplementation on hematologic and symptom-based outcomes.
Iron deficiency is one of the most common nutritional deficiencies globally. NAID often remains unrecognized despite its potential to cause fatigue, decreased physical performance, and progression to anemia if untreated. Iron plays a key role in oxygen transport, DNA synthesis, and muscle metabolism. Dietary intake includes both heme (animal-derived) and non-heme (plant-derived) forms with differing bioavailability. Ferritin is the primary biomarker used to diagnose iron deficiency, though inflammatory conditions may influence its accuracy. A careful differential evaluation is important to distinguish NAID from other causes of anemia such as chronic disease, B12 or folate deficiency, thalassemia syndromes, thyroid disorders, or gastrointestinal blood loss.
The study uses a two-phase, single-center prospective design at Kağıthane 5 No'lu Family Health Center (ASM), Istanbul, Turkey, conducted under ethics committee approval and institutional permission. In the initial two-month observational phase, participants receive standardized dietary counseling aimed at increasing iron intake and improving absorption. Health status and adherence are monitored biweekly. After this period, participants are categorized into four groups according to hematologic changes: isolated iron deficiency; microcytosis/hypochromia with minimal hemoglobin decline (<1 g/dL) ; greater hemoglobin decline without meeting anemia thresholds; or overt iron deficiency anemia.
In the subsequent one-month experimental phase, participants with persistent deficiency receive oral ferrous sulfate providing 80 mg elemental iron daily. Clinical and laboratory evaluations are performed at designated time points to assess changes in complete blood count parameters, ferritin, serum iron indices, inflammatory markers, and patient-reported symptoms.
Primary outcomes include changes in symptom scores, while secondary outcomes evaluate hematologic and biochemical responses. Planned analyses explore associations between baseline characteristics, dietary habits, and anemia progression. Power analysis using repeated measures ANOVA indicated a required sample size of 60 participants.
This research highlights the importance of individualized management strategies for iron deficiency, aiming to support appropriate use of supplementation while reducing unnecessary treatment and potential adverse effects. Enhancing dietary iron intake may help prevent anemia progression, promote patient safety, and improve resource utilization in primary care settings.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- All participants initially receive the same nutritional intervention; after post-intervention evaluation, subgroups are defined and those with persistent iron deficiency receive the drug intervention.
| Arm | Type | Receives |
|---|---|---|
| ARM 1 - Nutritional Intervention with Post-Intervention Subgrouping | Experimental | Other: Dietary Intervention (2 months), Drug: Oral Elemental Iron (Ferrous Sulfate) 80 mg/dayAll participants (N=60) begin with isolated non-anemic iron deficiency and receive a 2-month standardized nutritional intervention to improve iron intake and absorption. Afterward, participants are stratified into five subgroups (ARM1-0 to ARM1-4) based on hematologic response. Subgroups ARM1-1 to ARM1-4 represent persistent deficiency (ferritin <15 µg/L with normal CRP) and will receive oral elemental iron. * ARM1-0: Normalized or maintained iron status (no deficiency) - no iron therapy administered. * ARM1-1: Persistent isolated iron deficiency - receives oral elemental iron. * ARM1-2: Minimal hemoglobin decline (<1 g/dL) with microcytosis/hypochromia - receives oral elemental iron. * ARM1-3: Hemoglobin decline >1 g/dL but above anemia threshold, with microcytosis/hypochromia - receives oral elemental iron. * ARM1-4: Overt iron deficiency anemia - receives oral elemental iron. |
Who may qualify
- Ages
- 18 to 55 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (8 listed)
- Female participants aged 18-55 years (including premenopausal and menopausal women).
- Normal hemoglobin level (≥ 12 g/dL).
- Serum ferritin < 15 μg/L (WHO criteria for iron deficiency).
- Mentzer index > 13.
- Normal levels of vitamin B12, folic acid, thyroid hormones (TSH and sT4), and C-reactive protein (CRP < 5 mg/L).
Key exclusion criteria (12 listed)
- Pregnancy or postpartum period.
- Acute or chronic infections.
- History or suspicion of malignancy.
- Chronic inflammatory or autoimmune diseases.
- Chronic fatigue syndrome or depressive disorders.
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 |
|---|---|---|
| Dietary Intervention (2 months)Also: Nutritional Intervention (2 months)A two-month nutritional counseling program for all participants (N = 60) with isolated non-anemic iron deficiency. The program emphasized the inclusion of iron-rich foods (both heme and non-heme sources), the use of enhancers of iron absorption (such as vitamin C), and practical strategies to reduce absorption inhibitors (e.g., limiting tea and coffee consumption around meals, reviewing antacid use). Participants received biweekly phone follow-ups to monitor adherence and assess symptoms. | Other | ARM 1 - Nutritional Intervention with Post-Intervention Subgrouping |
| Oral Elemental Iron (Ferrous Sulfate) 80 mg/dayAlso: Oral Iron Intervention (1 month)One-month oral therapy with 80 mg elemental iron (ferrous sulfate) daily for participants with persistent iron deficiency after the nutritional phase (ferritin < 15 µg/L). Biweekly phone follow-up for adherence and symptom checks. Adherence and side effects monitored at clinic visit or by phone. | Drug | ARM 1 - Nutritional Intervention with Post-Intervention Subgrouping |
Primary outcome
Change from Baseline in Patient-Reported Iron Deficiency Symptom Scores After 2-Month Nutritional Intervention and 1-Month Oral Iron Therapy
Time frame: Baseline, Week 8 (post-nutritional intervention), Week 12 (post-oral iron therapy)
Change in patient-reported symptoms including fatigue, weakness, dizziness, and cognitive function etc. measured at baseline, after 2-month nutritional intervention, and after 1-month oral iron therapy.
5 secondary outcomes
Change from Baseline in Hemoglobin and Red Blood Cell Indices After 2-Month Nutritional Intervention and 1-Month Oral Iron Therapy
Time frame: Baseline, Week 8, Week 12
Change from Baseline in Serum Iron and Total Iron Binding Capacity After 2-Month Nutritional Intervention and 1-Month Oral Iron Therapy
Time frame: Baseline, Week 8, Week 12
Incidence of Progression to Anemia After 2-Month Nutritional Intervention
Time frame: Baseline to Week 8
Proportion of Participants Demonstrating Hematologic Response to 1-Month Oral Iron Therapy (Hb increase ≥1.0 g/dL)
Time frame: Week 8 to Week 12
Proportion of Participants Demonstrating Ferritin Response to 1-Month Oral Iron Therapy (Ferritin increase ≥15 µg/L or ≥30 µg/L absolute)
Time frame: Week 8 to Week 12
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 4 Dec 2025.
- Background: PubMed 20087382Ortancil O, Sanli A, Eryuksel R, Basaran A, Ankarali H. Association between serum ferritin level and fibromyalgia syndrome. Eur J Clin Nutr. 2010 Mar;64(3):308-12. doi: 10.1038/ejcn.2009.149. Epub 2010 Jan 20.
- Background: PubMed 35807904Skolmowska D, Glabska D, Kolota A, Guzek D. Effectiveness of Dietary Interventions to Treat Iron-Deficiency Anemia in Women: A Systematic Review of Randomized Controlled Trials. Nutrients. 2022 Jun 30;14(13):2724. doi: 10.3390/nu14132724.
- Results publication: PubMed 29611716Silva Neto LGR, Santos Neto JED, Bueno NB, de Oliveira SL, Ataide TDR. Effects of iron supplementation versus dietary iron on the nutritional iron status: Systematic review with meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr. 2019;59(16):2553-2561. doi: 10.1080/10408398.2018.1459469. Epub 2018 Apr 30.
- Results publication: PubMed 26289639Moretti D, Goede JS, Zeder C, Jiskra M, Chatzinakou V, Tjalsma H, Melse-Boonstra A, Brittenham G, Swinkels DW, Zimmermann MB. Oral iron supplements increase hepcidin and decrease iron absorption from daily or twice-daily doses in iron-depleted young women. Blood. 2015 Oct 22;126(17):1981-9. doi: 10.1182/blood-2015-05-642223. Epub 2015 Aug 19.
- Results publication: PubMed 37299583Stefan MW, Gundermann DM, Sharp MH, Jennings BA, Gheith RH, Lowery RP, LowDog T, Ghatak SB, Barbosa J, Wilson JM. Assessment of the Efficacy of a Low-Dose Iron Supplement in Restoring Iron Levels to Normal Range among Healthy Premenopausal Women with Iron Deficiency without Anemia. Nutrients. 2023 Jun 3;15(11):2620. doi: 10.3390/nu15112620.
- Results publication: PubMed 35905974Nemeth E, Ganz T. Hepcidin and Iron in Health and Disease. Annu Rev Med. 2023 Jan 27;74:261-277. doi: 10.1146/annurev-med-043021-032816. Epub 2022 Jul 29.
- Results publication: PubMed 32425874Zhu XY, Wu TT, Wang HM, Li X, Ni LY, Chen TJ, Qiu MY, Shen J, Liu T, Ondo WG, Wu YC. Correlates of Nonanemic Iron Deficiency in Restless Legs Syndrome. Front Neurol. 2020 Apr 30;11:298. doi: 10.3389/fneur.2020.00298. eCollection 2020.
- Results publication: PubMed 24756645Sawada T, Konomi A, Yokoi K. Iron deficiency without anemia is associated with anger and fatigue in young Japanese women. Biol Trace Elem Res. 2014 Jun;159(1-3):22-31. doi: 10.1007/s12011-014-9963-1. Epub 2014 Apr 23.
- Results publication: PubMed 34564844da Silva Lopes K, Yamaji N, Rahman MO, Suto M, Takemoto Y, Garcia-Casal MN, Ota E. Nutrition-specific interventions for preventing and controlling anaemia throughout the life cycle: an overview of systematic reviews. Cochrane Database Syst Rev. 2021 Sep 26;9(9):CD013092. doi: 10.1002/14651858.CD013092.pub2.
- Results publication: PubMed 31860749Miles LF, Litton E, Imberger G, Story D. Intravenous iron therapy for non-anaemic, iron-deficient adults. Cochrane Database Syst Rev. 2019 Dec 20;12(12):CD013084. doi: 10.1002/14651858.CD013084.pub2.
- Results publication: PubMed 29626044Houston BL, Hurrie D, Graham J, Perija B, Rimmer E, Rabbani R, Bernstein CN, Turgeon AF, Fergusson DA, Houston DS, Abou-Setta AM, Zarychanski R. Efficacy of iron supplementation on fatigue and physical capacity in non-anaemic iron-deficient adults: a systematic review of randomised controlled trials. BMJ Open. 2018 Apr 5;8(4):e019240. doi: 10.1136/bmjopen-2017-019240.
- Results publication: PubMed 34693519Fletcher A, Forbes A, Svenson N, Wayne Thomas D; A British Society for Haematology Good Practice Paper. Guideline for the laboratory diagnosis of iron deficiency in adults (excluding pregnancy) and children. Br J Haematol. 2022 Feb;196(3):523-529. doi: 10.1111/bjh.17900. Epub 2021 Oct 24. No abstract available.
- Ethical approval: Istanbul University-Cerrahpasa Clinical Research Ethics Committee.Link provided by the sponsor.
- Institutional authorization: Permission for study implementation obtained from Istanbul Provincial Health Directorate.Link provided by the sponsor.
- Individual participant dataSharing planned: No
Related trials for Non-Anemic Iron Deficiency
Active, not recruiting
Absorption of Iron From Stabilized Lactoferrin: A Study in Women With Iron Deficiency
Iron Deficiency (Without Anemia)
Active, not recruiting
The Immediate and Long-term Effects of a Novel Marine-based Iron Supplement in Adult Females
Anemia, Iron Deficiency (Without Anemia)
RecruitingObservational study
Non-invasive Detection of Iron Deficiency in Obstetrics
Iron Deficiency Anemia of Pregnancy, Iron-deficiency
Recruiting
Effect of Chitin and Ascorbic Acid on Dietary Insect Iron Absorption
Iron Deficiency (Without Anemia)
RecruitingObservational study
Iron Status of Non-anemic Pregnant Women in First Trimester
Iron Deficiency (Without Anemia), Reference Values
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.
Osman Demir, MD principal investigator
Kağıthane No.5 Family Health Center, Istanbul, Turkey
Ayşen Fenercioğlu, Assoc Prof study director
Istanbul University - Cerrahpaşa, Cerrahpaşa Faculty of Medicine
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Dietary Intervention (2 months) and Oral Elemental Iron (Ferrous Sulfate) 80 mg/day in people with Non-Anemic Iron Deficiency, run by Istanbul University - Cerrahpasa at 1 site in Turkey (Türkiye).
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 8 inclusion and 12 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 4 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). 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 Osman Demir, MD (+90 532 291 4470, osman.demir@iuc.edu.tr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change from Baseline in Patient-Reported Iron Deficiency Symptom Scores After 2-Month Nutritional Intervention and 1-Month Oral Iron Therapy (time frame: Baseline, Week 8 (post-nutritional intervention), Week 12 (post-oral iron therapy)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07263529, which also lists 17 linked publications.
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 4 Dec 2025.