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Retinol Equivalence of Plant Carotenoids in Children

This study has been completed.
Information provided by:
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Identifier:
First received: May 6, 2004
Last updated: January 12, 2010
Last verified: January 2010

To determine vitamin A value of beta-carotene in oil capsule, spinach, and golden rice.

The experiments will be conducted in children (ages 7-9) with/without adequate 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, deca-deuterated retinyl acetate (RAc-d10), to evaluate the bioavailability and the bioconversion of plant provitamin A carotenes to retinol as compared with ß-C in oil capsules in vivo.

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.

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.

Vitamin A Deficiency

Study Type: Observational
Study Design: Observational Model: Case-Only

Resource links provided by NLM:

Further study details as provided by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK):

Enrollment: 32
Study Start Date: September 2004
Study Completion Date: November 2005
Detailed Description:
Seventy-two children each will take two meals, lunch and supper, containing equal amounts of ß-C in labeled spinach (along with white rice), or Golden Rice (along with light colored vegetables), or ß-C oil capsules (along with white rice and light colored vegetables), every day for 7 days. Before the two meals, the volunteers will take a breakfast with a RAc-d10 dose as a reference for 7 days. 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.

Ages Eligible for Study:   7 Years to 9 Years   (Child)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
healthy children with normal or marginal vitamin A nutrition

Inclusion Criteria:

  • 7-9 years old

Exclusion Criteria:

  • Parasitic infection
  Contacts and Locations
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No Contacts or Locations Provided
  More Information

Lei Li, Yin Wang, Shi-an Yin, Michael A Grusak, Robert M Russell, Guangwen Tang. Bioconversion of spinach β-carotene in Chinese children with noemal or marginal vitamin A status. FASEB J. 2006 20:A1319
Lei Li, Yin Wang, Jieshu Wu, Ranfeng Zhu, Xianfeng Zhao, Zhixu Wang, Shi-an Yin. Biefficacy of β-carotene in Chinese children with marginal and normal vitamin A status (in Chinese). Hygiene Research, 2007;36(5):547-551. Identifier: NCT00082420     History of Changes
Obsolete Identifiers: NCT00072696
Other Study ID Numbers: RETEQ (completed)
Study First Received: May 6, 2004
Last Updated: January 12, 2010

Keywords provided by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK):
Vitamin A malnutrition
low vitamin A status

Additional relevant MeSH terms:
Vitamin A Deficiency
Night Blindness
Deficiency Diseases
Nutrition Disorders
Vision Disorders
Eye Diseases
Vitamin A
Growth Substances
Physiological Effects of Drugs processed this record on August 22, 2017