Effects of Enhancers and Inhibitors on Absorption From Iron Supplements

Not Applicable

Completed

• Conditions: Iron Deficiency Anemia; Iron-deficiency
• Interventions: Other: Reference; Other: Afternoon; Other: Coffee; Other: Breakfast; Other: Ascorbic acid (AA) 500 mg; Other: Ascorbic acid (AA) 80 mg

• Registration Number: NCT05414474
• Lead Sponsor: Swiss Federal Institute of Technology

Brief Summary

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.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2022-05-13
• Study First Submitted QC: 2022-06-09
• Study First Posted: 2022-06-10
• Study Start: 2022-06-20
• Primary Completion: 2022-12-09
• Study Completion: 2022-12-09
• Status Verified: 2024-01
• Last Update Submitted: 2024-01-23
• Last Update Posted: 2024-01-25

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 35

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.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Reference	Reference	Ferrum Hausmann 100 mg is consumed with 200 mL nanopure water with labelled ferrous fumarate (3 mg 54Fe).
Afternoon	Afternoon	Ferrum Hausmann 100 mg is consumed with 200 mL nanopure water with labelled ferrous fumarate (3 mg 58Fe) in the afternoon .
Coffee	Coffee	Ferrum Hausmann 100 mg is consumed with 200 mL nanopure water with labelled ferrous fumarate (3 mg 54Fe) and 150 mL coffee.
Breakfast	Breakfast	Ferrum Hausmann 100 mg is consumed with 200 mL nanopure water with labelled ferrous fumarate (3 mg 57Fe) and 1 bread roll (\~100 g) with butter and honey, 1 cup of plain yoghurt (180 mL), 1 cup of coffee (150 mL) and 1 glass of orange juice (250 mL).
Ascorbic acid (AA) 500 mg	Ascorbic acid (AA) 500 mg	Ferrum Hausmann 100 mg is consumed with 200 mL nanopure water with labelled ferrous fumarate (3 mg 57Fe) and 500 mg AA.
Ascorbic acid (AA) 80 mg	Ascorbic acid (AA) 80 mg	Ferrum Hausmann 100 mg is consumed with 200 mL nanopure water with labelled ferrous fumarate (3 mg 58Fe) and 80 mg AA.

Primary Outcome Measures

Name	Time	Method
Fractional iron absorption [percent]	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.
Total iron absorption [mg]	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 Outcome Measures

Name	Time	Method
Hemoglobin (Hb)	Day 1, 22, 26 and 43	Iron status marker
Alpha-1-acid-glycoprotein (AGP)	Day 1, 22, 26 and 43	Inflammation marker
Hepcidin	Day 1, 22 and 26	Iron regulatory protein
Serum ferritin (SF)	Day 1, 22, 26 and 43	Iron status marker
Serum transferrin receptor (sTfR)	Day 1, 22, 26 and 43	Iron status marker
Serum iron (SFe)	Day 1, 22, 26 and 43	Iron status marker
Total iron binding capacity (TIBC)	Day 1, 22, 26 and 43	Iron status marker
C-reactive protein (CRP)	Day 1, 22, 26 and 43	Inflammation marker

Trial Locations

Locations (1)

ETH Zurich; Human Nutrition Laboratory; Institute of Food, Nutrition and Health; 🇨🇭 Zürich, Switzerland