Bioavailability of Yellow Maize Carotenoids in Humans

NCT ID: NCT00636038

Last Updated: 2008-03-14

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE1
• Total Enrollment: 8 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2008-01-31
• Study Completion Date: 2008-03-31

Brief Summary

The study hypothesis is that high ß-C yellow maize can provide vitamin A efficiently.

• list item one ß-C in yellow maize

The study will use stable isotope labeled high ß-C yellow maize and vitamin A in a well-nourished population by utilizing stable isotope dilution techniques. In this project, deuterium labeled vitamin A that is derived from the labeled ß-C yellow maize will be traced after being eaten by a human subject. Eight men (> 40 years and < 70 y) who are healthy, non-smoking,body weight within 20% of standard weight for height (Metropolitan) and not having taken vitamin A or ß-C supplements within the last month will be recruited as volunteers. This study will last for 50 days during which at day 1, cooked labeled yellow maize paste (porridge) equal to a total of ~ 2 bowls cooked yellow maize (from 100 - 200 g dry weight) containing ~ 1 mg ß-C will be taken by each volunteer. On day 8, a labeled vitamin A (1 mg of 13C retinyl acetate) in oil dose will be used in evaluation of liver storage of vitamin A. Forty six blood samples (460 cc) will be taken during the study which will be analyzed for serum carotenoids and retinoids using HPLC and mass spectrometry techniques.

The serum concentration and isotope ratio of ß-C and retinol will be determined. Serum enrichment curve following each oral dose will be studied. The area under the curve (AUC) of retinol-d4 and labeled retinol from the reference dose in serum samples will be determined and compared. The equivalence of a high ß-C corn meal to vitamin A will be calculated based on the isotope reference method to determine the efficiency of corn ß-C to provide vitamin A.

Detailed Description

• list item one ß-C in yellow maize

Pro-vitamin A carotenoids in plants are a major and safe vitamin A source for a vast population in the world. Even though, ß-carotene (ß-C) in vegetables has been considered as a safe vitamin A source, it is essential to determine the efficiency of provitamin A carotenoids in plant conversion to vitamin A. However, the bioavailability of vitamin A and carotenoids from food matrices has not been well studied due to the unavailability of isotopically labeled foods that can be fed to humans.

The main objective of this study is to investigate the bioavailability of ß-C in yellow maize and its bioconversion to retinol stored in the liver using stable isotope labeled high ß-C yellow maize and vitamin A in a well-nourished population by utilizing stable isotope dilution techniques. In this project, the deuterium labeled vitamin A that is derived from the labeled ß-C yellow maize will be traced after being eaten by a human subject. This will allow for quantitative determination of the vitamin A equivalence of high ß-C plant foods.

Eight men (> 40 years and < 70 y) who are healthy, non-smoking adults must have their body weight within 20% of standard weight for height (Metropolitan) and not having taken vitamin A or ß-C supplements within the last month will be recruited as volunteers.

This is a 50 day study during which dose 1, cooked labeled yellow maize paste (porridge) equal to a total of ~ 2 bowls cooked yellow maize (from 100 - 200 g dry weight) containing ~ 1 mg ß-C will be taken by each volunteer. On day 8, dose 2 will be used in evaluation of liver storage of vitamin A using 1 mg of 13C retinyl acetate. One blood sample (20 cc) will be drawn during the screening process. Forty six blood samples (460 cc) will be taken during the study which will be analyzed for serum carotenoids and retinoids using HPLC and mass spectrometry techniques. The serum concentration and isotope ratio of ß-C and retinol will be determined. Serum enrichment curve following each oral dose will be studied. The area under the curve (AUC) of retinol-d4 and labeled retinol from the reference dose in serum samples will be determined and compared. The equivalence of a high ß-C plant food supplement to a vitamin A dose will be calculated based on the isotope reference method.

Conditions

Vitamin A Status

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Interventions

corn beta-carotene

yellow corn beta-carotene in a 1 mg level to be taken as corn porridge in one meal by volunteers

Intervention Type: DIETARY_SUPPLEMENT

Other Intervention Names

staple food beta-carotene

Eligibility Criteria

Inclusion Criteria

• healthy subjects

Exclusion Criteria

• GI track problems

• Minimum Eligible Age: 40 Years
• Maximum Eligible Age: 70 Years
• Eligible Sex: MALE
• Accepts Healthy Volunteers: Yes

Sponsors

Nutricia Research Fundation

OTHER

Sponsor Role: collaborator

National University of Science and Technology, Zimbabwe

OTHER

Sponsor Role: collaborator

Tufts University

OTHER

Sponsor Role: lead

Responsible Party

Tufts University

Locations

National University of Science and Technology

Bulawayo, , Zimbabwe

Countries

Zimbabwe

References

Muzhingi T, Gadaga TH, Siwela AH, Grusak MA, Russell RM, Tang G. Yellow maize with high beta-carotene is an effective source of vitamin A in healthy Zimbabwean men. Am J Clin Nutr. 2011 Aug;94(2):510-9. doi: 10.3945/ajcn.110.006486. Epub 2011 Jun 29.

Reference Type: DERIVED

PMID: 21715509 (View on PubMed)

Other Identifiers

2007-E6

Identifier Type: -

Identifier Source: org_study_id