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Effects of Vitamin A and Carotenoids on Iron Absorption

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ClinicalTrials.gov Identifier: NCT01493297
Recruitment Status : Completed
First Posted : December 15, 2011
Last Update Posted : January 23, 2014
Sponsor:
Collaborator:
Instituto Venezolano de Investigaciones Cientificas
Information provided by (Responsible Party):
Prof. Michael B. Zimmermann, Swiss Federal Institute of Technology

Brief Summary:
The objective of this study is to investigate the effect of vitamin A and carotenoids on iron absorption in healthy subjects with low and normal vitamin A status. Vitamin A and carotenoids have been reported to enhance the nonheme iron absorption, but the results from human isotope studies are equivocal. Radio-iron studies in Venezuelan adults have consistently reported an increase in iron absorption, whereas stable and radio isotopes studies conducted in Sweden and Switzerland reported no influence. Differences in vitamin A status of the subjects may be a possible explanation for the contradictory findings. In this study, iron absorption will be measured from an iron-fortified maize bread meal with or without retinyl palmitate or β-carotene by using both stable- and radioactive-isotope techniques in Venezuelan women with a range of vitamin A status.

Condition or disease Intervention/treatment Phase
Iron Absorption Other: Labeled iron solutions Not Applicable

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 25 participants
Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: Single (Participant)
Primary Purpose: Basic Science
Official Title: Effects of Vitamin A and Carotenoids on Iron Absorption
Study Start Date : September 2011
Actual Primary Completion Date : November 2011
Actual Study Completion Date : July 2012

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Iron Vitamin A
U.S. FDA Resources

Arm Intervention/treatment
Retinyl palmitate
Labeled iron as FeSO4 (4 mg) added to a test meal with or without retinyl palmitate (1000 RE)
Other: Labeled iron solutions
Labeled iron as FeSO4 (4 mg/test meal)
Beta-carotene
Labeled iron as FeSO4 (4 mg) added to a test meal with or without beta-carotene (1000 RE)
Other: Labeled iron solutions
Labeled iron as FeSO4 (4 mg/test meal)



Primary Outcome Measures :
  1. Fractional iron absorption [ Time Frame: 1 month after enrollment ]
    Iron absorption will be estimated by measuring the erythrocyte incorporation of stable (57Fe/58Fe) and radio (55Fe/59Fe) iron isotopes labels given in test meals.



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Ages Eligible for Study:   18 Years to 52 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Women 18-52 years old
  • Body weight ≤ 70 kg
  • Body mass index (BMI), 18.5-30 kg/m2
  • Adequate vitamin A status (SR ≥ 0.7 μmol/L, n=20)
  • Inadequate vitamin A status (SR < 0.7 μmol/L, n=20)
  • No major medical illnesses (no known infection, gastrointestinal or metabolic disorders)

Exclusion Criteria:

  • Pregnancy or lactation
  • Regular intake of medication (except oral contraceptives)
  • Blood donation or significant blood loss (accident, surgery) over the past 4 months
  • Currently participating in another clinical trial or having participated in another clinical trial during the last 3 months prior to the beginning of this study
  • Former participation in a study involving administration of iron stable isotopes

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01493297


Locations
Venezuela
Venezuelan Institute for Scientific Research (IVIC)
Caracas, Venezuela, 1020-A
Sponsors and Collaborators
Swiss Federal Institute of Technology
Instituto Venezolano de Investigaciones Cientificas
Investigators
Principal Investigator: Maria Andersson, Dr Swiss Federal Institute of Technology, ETH Zurich

Publications:
Garcia-Casal MN. Carotenoids increase iron absorption from cereal based food in the human. Nutr Res 2006;26:340-4.
Layrisse M, Garcia-Casal MN, Solano L, et al. The role of vitamin A on the inhibitors of nonheme iron absorption: preliminary results. J Nutr Biochem 1997;8:61-7.

Responsible Party: Prof. Michael B. Zimmermann, Principal investigator, Swiss Federal Institute of Technology
ClinicalTrials.gov Identifier: NCT01493297     History of Changes
Other Study ID Numbers: ETH-FeVZ
First Posted: December 15, 2011    Key Record Dates
Last Update Posted: January 23, 2014
Last Verified: January 2014

Keywords provided by Prof. Michael B. Zimmermann, Swiss Federal Institute of Technology:
Retinyl palmitate, beta-carotene, stable isotopes, radio isotopes

Additional relevant MeSH terms:
Iron
Vitamin A
Beta Carotene
Carotenoids
Retinol palmitate
Trace Elements
Micronutrients
Growth Substances
Physiological Effects of Drugs
Vitamins
Antioxidants
Molecular Mechanisms of Pharmacological Action
Protective Agents
Provitamins
Anticarcinogenic Agents
Antineoplastic Agents