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The CARO Study - Bioefficacy of Beta-Carotene in Oil and in a Mixed Diet in Healthy Subjects

NCT ID: NCT00128752

Last Updated: 2005-08-29

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

24 participants

Study Classification

INTERVENTIONAL

Study Start Date

2003-03-31

Study Completion Date

2003-10-31

Brief Summary

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A controlled dietary intervention study will be carried out based on the stable isotope method the investigators have developed to quantify both the absorption of beta-carotene and its bioconversion to retinol in oil and in a mixed diet. For 6 weeks the participants will consume 2 capsules/day, 7 days/week with each capsule containing 50-mg \[13C10\] beta-carotene and 50-mg \[13C10\] retinyl palmitate. For three weeks they will consume a diet with high levels of beta-carotene in vegetables and fruits and for the other 3 weeks they will consume a diet with low levels of beta-carotene in vegetables and fruits supplemented with an extra amount of beta-carotene in oil. Samples of blood and faeces will be taken.

The study hypothesis is that the absorption of beta-carotene in oil in comparison with the absorption of beta-carotene in a mixed diet differs by a factor of 3 to 6. The investigators want to measure the influence of the food matrix of vegetables and fruits on the absorption of beta-carotene in healthy humans on a western diet.

Detailed Description

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Conditions

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Healthy

Keywords

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vitamin A beta Carotene diet nutrition nutritional requirements

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

CROSSOVER

Primary Study Purpose

PREVENTION

Blinding Strategy

NONE

Interventions

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absorption and conversion of beta-carotene in human gastrointestinal (GI) tract

Intervention Type BEHAVIORAL

Eligibility Criteria

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Inclusion Criteria

* Men and women between 18 and 50 years old
* Body mass index (BMI) between 18 and 25 kg/m2
* Willing to consume the controlled diet and not consume other food items
* Willing to consume the cooked meal at the research facility and the bread meals and snacks at home (distributed to the participants)
* Willing to consume the capsules every day

Exclusion Criteria

* Hematological diseases and chronic diseases including cancer, renal insufficiency, liver disease, diagnosed gastrointestinal disorders, or surgery of the gastrointestinal tract
* Use of (oral) drugs suspected of interfering with fat-soluble-vitamin absorption
* Smoking
* Excessive alcohol consumption (\>30 g/d)
* Consumption of vitamin or carotenoid supplements 6 weeks before and during the study
* Not too low or high levels of serum beta-carotene and retinol
* Normal hemoglobin, hemocytometry, creatinine, ALAT, alkaline phosphatase, and cholesterol blood values (compared with laboratory references)
* Pregnancy
Minimum Eligible Age

18 Years

Maximum Eligible Age

50 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

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Dutch Dairy Organization (NZO)

OTHER

Sponsor Role collaborator

Radboud University Medical Center

OTHER

Sponsor Role lead

Principal Investigators

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Ton HJ Naber, MD PhD

Role: STUDY_DIRECTOR

Radboud University Medical Center

Clive E West, PhD DSc

Role: PRINCIPAL_INVESTIGATOR

Radboud University Medical Center

Carolien A Bouwman, MSc

Role: STUDY_CHAIR

Radboud University Medical Center

Locations

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Radboud University Nijmegen Medical Centre

Nijmegen, Gelderland, Netherlands

Site Status

Countries

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Netherlands

References

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van Lieshout M, West CE, Muhilal, Permaesih D, Wang Y, Xu X, van Breemen RB, Creemers AF, Verhoeven MA, Lugtenburg J. Bioefficacy of beta-carotene dissolved in oil studied in children in Indonesia. Am J Clin Nutr. 2001 May;73(5):949-58. doi: 10.1093/ajcn/73.5.949.

Reference Type BACKGROUND
PMID: 11333850 (View on PubMed)

van Lieshout M, West CE, van Breemen RB. Isotopic tracer techniques for studying the bioavailability and bioefficacy of dietary carotenoids, particularly beta-carotene, in humans: a review. Am J Clin Nutr. 2003 Jan;77(1):12-28. doi: 10.1093/ajcn/77.1.12.

Reference Type BACKGROUND
PMID: 12499318 (View on PubMed)

West CE, Eilander A, van Lieshout M. Consequences of revised estimates of carotenoid bioefficacy for dietary control of vitamin A deficiency in developing countries. J Nutr. 2002 Sep;132(9 Suppl):2920S-2926S. doi: 10.1093/jn/132.9.2920S.

Reference Type BACKGROUND
PMID: 12221270 (View on PubMed)

Van Loo-Bouwman CA, West CE, van Breemen RB, Zhu D, Siebelink E, Versloot P, Hulshof PJ, van Lieshout M, Russel FG, Schaafsma G, Naber TH. Vitamin A equivalency of beta-carotene in healthy adults: limitation of the extrinsic dual-isotope dilution technique to measure matrix effect. Br J Nutr. 2009 Jun;101(12):1837-45. doi: 10.1017/S0007114508131762. Epub 2008 Nov 24.

Reference Type DERIVED
PMID: 19025719 (View on PubMed)

Other Identifiers

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NZO-2002-07

Identifier Type: -

Identifier Source: secondary_id

CARO-2002-12-12-NZO

Identifier Type: -

Identifier Source: org_study_id