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Vitamin A Equivalence of Plant Carotenoids in Children

This study has been completed.
Information provided by:
Tufts University Identifier:
First received: May 16, 2008
Last updated: February 17, 2009
Last verified: February 2009
Our objectives will be to test the following hypotheses and to make the following determinations: (1) The absorption and bio-conversion of provitamin A carotenes taken by children are different between spinach, Golden Rice, and ß-C in oil capsules. (2) The absorption of provitamin A carotenes and their bioconversion to vitamin A are different in children with or without adequate vitamin A nutrition. (3) To define the vitamin A equivalence(s) of dietary spinach, Golden Rice, and a ß-C in oil dose by using an isotope reference method in children with or without adequate vitamin A nutrition and to compare those values with values derived from model based compartmental analysis. (4) To determine the number and time of blood samples needed for future studies in various field settings on the retinol equivalence of a large number of plant sources.

Condition Intervention Phase
Vitamin A Deficiency Dietary Supplement: dietary carotenoids Dietary Supplement: spinach, rice, and synthetic beta-carotene Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science

Resource links provided by NLM:

Further study details as provided by Tufts University:

Primary Outcome Measures:
  • conversion efficiency of b-C to retinol [ Time Frame: up to 21 days ]

Estimated Enrollment: 72
Study Start Date: July 2008
Study Completion Date: January 2009
Primary Completion Date: January 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
dietary carotenoids
Dietary Supplement: dietary carotenoids
spinach containing 1 - 2 mg beta-carotene rice containing 0.5 mg beta-carotene synthetic beta-carotene 0.5 mg oil capsule
Dietary Supplement: spinach, rice, and synthetic beta-carotene
spinach containing 1 - 2 mg beta-carotene rice containing 0.5 mg beta-carotene synthetic beta-carotene, 0.5 mg oil dose
Other Name: dietary carotenoids

Detailed Description:

This project is to determine the vitamin A value (equivalence) of dietary provitamin A carotenes from spinach, Golden Rice, and pure ß-carotene (ß-C) in oil. These experiments will be conducted in children (ages 6-8) with/without adequate (marginal deficiency) vitamin A nutrition. As plant provitamin A carotenoids are a major and safe vitamin A source for a vast population in the world, it is essential to determine the efficiency of provitamin A carotenoid (mainly ß-C) conversion to vitamin A. By introducing ß-C into rice endosperm, Golden Rice may directly benefit consumers by providing vitamin A nutrition. Our investigation uses hydroponically grown, deca-deuterium labeled spinach and Golden Rice, synthetic ß-C-d10 and a vitamin A isotope reference, C13 labeled retinyl acetate (13C10-RAc), to evaluate the bioavailability and the bioconversion of plant provitamin A carotenes to retinol as compared with ß-C in oil capsules in vivo.

Seventy-two children each will take two meals, breakfast containing 13C10-RAc dose (0.5mg in 0.2g oil capsule) and lunch containing spinach containing 1 mg ß-C (along with white rice), or Golden Rice containing 0.5mg ß-C (along with light colored vegetables), or ß-C oil capsules containing 0.5 mg ß-C in 0.2g oil (along with white rice and light colored vegetables) on the first day of the study. Blood samples will be collected at 1 3, 7, 14, and 21 days after the study doses.

The enrichment of labeled ß-C and labeled retinol in human circulation will be determined using advanced liquid chromatography / mass spectrometry and gas chromatography / mass spectrometry. Through the applications of these novel technologies, we will be able to determine the relative biological activities of endogenous carotenoids; that is, the vitamin A value of spinach, Golden Rice, and ß-C in oil capsules for children with/without vitamin A malnutrition.

This study will be of importance in planning vitamin A deficiency prevention strategies and also will provide useful information regarding the potential efficacy of a bioengineered crop to provide vitamin A nutrition.


Ages Eligible for Study:   6 Years to 8 Years   (Child)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • healthy children

Exclusion Criteria:

  • food allergy
  • parasitic infection
  Contacts and Locations
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Please refer to this study by its identifier: NCT00680212

United States, Massachusetts
USDA Human Nutrition Research Center on Aging, Tufts Uni.
Boston, Massachusetts, United States, 02111
Sponsors and Collaborators
Tufts University
Principal Investigator: Guangwen Tang, Ph. D Tufts University
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Guangwen Tang, Tufts University Identifier: NCT00680212     History of Changes
Other Study ID Numbers: IRB 8458
R01DK060021 ( U.S. NIH Grant/Contract )
Study First Received: May 16, 2008
Last Updated: February 17, 2009

Keywords provided by Tufts University:
dietary beta-carotene
vitamin A status
intrinsically labeled plant foods

Additional relevant MeSH terms:
Vision Disorders
Vitamin A Deficiency
Night Blindness
Deficiency Diseases
Nutrition Disorders
Eye Diseases
Vitamin A
Beta Carotene
Retinol palmitate
Growth Substances
Physiological Effects of Drugs
Molecular Mechanisms of Pharmacological Action
Protective Agents
Anticarcinogenic Agents
Antineoplastic Agents processed this record on September 21, 2017