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Completed

NCT Number: NCT05414474

Effects of Enhancers and Inhibitors on Absorption From Iron Supplements

Iron deficiency (ID) is a major public health problem worldwide and oral iron supplementation can be an effective strategy to treat and prevent ID. To maximize iron bioavailability form oral iron supplements the simultaneous intake of the iron absorption enhancer ascorbic acid (AA) is recommended, and the simultaneous intake of coffee or tea containing the iron absorption inhibitors polyphenols should be avoided. Also, oral iron supplements are recommended to be taken on an empty stomach in the morning and without a meal to avoid any interaction with phytic acid, another iron absorption inhibitor present in many foods. However, the effects of these iron absorption enhancers and inhibitors have only been shown on iron absorption from dietary iron (up to 10mg). Also, the effect of the diurnal hepcidin increase on absorption from an iron supplement given in the afternoon without a preceding morning dose is unclear. Whether AA also increases iron bioavailability from a supplemental iron dose and whether a cup of coffee, a breakfast or iron administration in the afternoon decreases iron bioavailability from a supplemental dose is uncertain.

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Key information

Conditions

Iron-deficiency Anemia Anemia, Hypochromic Anemia, Iron-Deficiency Hematologic Diseases Hemic and Lymphatic Diseases Iron Deficiencies Iron Deficiency Anemia Iron Metabolism Disorders Metabolic Diseases Nutritional and Metabolic Diseases

Age range

18 year–45 year

Sex eligibility

Female

Study type

Interventional

Phase

Not applicable

Primary location

ETH Zurich; Human Nutrition Laboratory; Institute of Food, Nutrition and Health

Zurich, 8092, Switzerland

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Female, 18 to 45 years old,
  • SF levels <30 μg/L,
  • Body weight < 70 kg
  • Normal Body Mass Index (18.5-25 kg/m2),
  • Signed informed consent.

Exclusion criteria

  • Anemia (Hb < 12 g/dL)
  • Elevated CRP > 5 mg/L,
  • Any metabolic, gastrointestinal, kidney or chronic disease such as diabetes, renal failure, hepatic dysfunction, hepatitis, hypertension, cancer or cardiovascular diseases (according to the participants own statement) affecting iron metabolism,
  • Continuous/long-term use of medication during the whole study, which may interfere with iron absorption, gut physiology and iron metabolism,
  • Consumption of mineral and vitamin supplements since screening and over the study period until last blood sample collection,
  • Difficulties with blood sampling,
  • Blood transfusion, blood donation or significant blood loss (accident, surgery) over the past 6 months,
  • Known hypersensitivity or allergy to iron capsules in the given amount (ferrous fumarate, brilliant blue FCF (E133), titandioxide (E171) and sodium lauryl sulfate)
  • Pregnancy, breastfeeding
  • Women who intend to become pregnant during the course of the study,
  • Known or suspected non-compliance, drug or alcohol (more than 2 drinks/day) abuse,
  • Smokers (> 1 cigarette per week),
  • Participant is likely to be absent on one the study appointments,
  • Inability to follow the procedures of the study, e.g. due to language problems, self-reported psychological disorders, etc. of the participant.

Treatment and study plan

reference

Other

Ferrum Hausmann 100 mg + 200 mL nanopure water with 3 mg 54Fe isotopes

Ascorbic acid (AA) 500 mg

Other

Ferrum Hausmann 100 mg + 200 mL nanopure water with 3 mg 57Fe isotopes + 500 mg AA

Ascorbic acid (AA) 80 mg

Other

Ferrum Hausmann 100 mg + 200 mL nanopure water with 3 mg 58Fe + 80 mg AA

Coffee

Other

Ferrum Hausmann 100 mg + 200 mL nanopure water with 3 mg 54Fe isotopes + 150 mL coffee

Breakfast

Other

Ferrum Hausmann 100 mg + 200 mL nanopure water with 3 mg 57Fe isotopes + 1 bread roll (~100 g) with butter and honey + 1 cup of plain yoghurt (180 mL) + 1 cup of coffee (150 mL) + 1 glass of orange juice (250 mL)

Afternoon

Other

Ferrum Hausmann 100 mg + 200 mL nanopure water with 3 mg 58Fe isotopes administered in the afternoon

Primary outcomes

  1. Fractional iron absorption [percent]

    Time frame: Day 22

    Fractional iron absorption will be calculated based on the shift of the iron isotope ratios in the collected blood samples after the administration of the intervention products. Fractional iron absorption will be measured as erythrocyte incorporation of the naturally occurring iron forms with different masses used to label the iron supplements.

  2. Fractional iron absorption [percent]

    Time frame: Day 43

    Fractional iron absorption will be calculated based on the shift of the iron isotope ratios in the collected blood samples after the administration of the intervention products. Fractional iron absorption will be measured as erythrocyte incorporation of the naturally occurring iron forms with different masses used to label the iron supplements.

  3. Total iron absorption [mg]

    Time frame: Day 22

    Total iron absorption will be calculated based on the shift of the iron isotope ratios in the collected blood samples after the administration of the intervention products. Total iron absorption will be measured as erythrocyte incorporation of the naturally occurring iron forms with different masses used to label the iron supplements.

  4. Total iron absorption [mg]

    Time frame: Day 43

    Total iron absorption will be calculated based on the shift of the iron isotope ratios in the collected blood samples after the administration of the intervention products. Total iron absorption will be measured as erythrocyte incorporation of the naturally occurring iron forms with different masses used to label the iron supplements.

Secondary outcomes

  1. Hemoglobin (Hb)

    Time frame: Day 1, 22, 26 and 43

    Iron status marker

  2. Serum ferritin (SF)

    Time frame: Day 1, 22, 26 and 43

    Iron status marker

  3. Serum transferrin receptor (sTfR)

    Time frame: Day 1, 22, 26 and 43

    Iron status marker

  4. Serum iron (SFe)

    Time frame: Day 1, 22, 26 and 43

    Iron status marker

  5. Total iron binding capacity (TIBC)

    Time frame: Day 1, 22, 26 and 43

    Iron status marker

  6. Hepcidin

    Time frame: Day 1, 22 and 26

    Iron regulatory protein

  7. C-reactive protein (CRP)

    Time frame: Day 1, 22, 26 and 43

    Inflammation marker

  8. Alpha-1-acid-glycoprotein (AGP)

    Time frame: Day 1, 22, 26 and 43

    Inflammation marker

Sponsors and collaborators

Lead sponsor

Swiss Federal Institute of Technology

Other

Registry information

Official study title

Effects of Nutritional Iron Absorption Enhancers and Inhibitors and Daytime on Absorption From Oral Iron Supplements

Important dates

Study start
2022
Primary completion
2022
Study completion
2022
First posted
Jun 10, 2022
Registry last updated
Jan 25, 2024

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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