Clinical trial NCT00680355: Bioavailability of Golden Rice Carotenoids in Humans
Official title: Bioavailability of Golden Rice Carotenoids in Humans
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: golden rice carotenoids
healthy volunteers
retinol equivalence
Lead sponsor: Tufts University
Sponsor class: OTHER
First posted: 2008-05-20
Enrollment: 14
Sex: ALL
Minimum age (years): 40
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

Brief summary: This investigation protocol uses an isotope reference method to evaluate bioavailability of ß-C in rice and its bioconversion to vitamin A.

A well-nourished population will be fed hydroponically grown Golden Rice containing \~ 1 mg of β-carotene at day 8 after a reference dose of vitamin A at day 1. The blood samples will be collected up to 33 days after the doses. The absorption kinetics will be determined by tracking both vitamin A and β-carotene in human serum. Blood responses to Golden Rice β-carotene will be determined and evaluated. The vitamin A value of Golden Rice can thus be quantitatively determined.

Detailed description: Recently, scientists have genetically engineered "golden rice" that contains 1.6 ug ß-carotene in a gram of dry rice (12). Since the vitamin A equivalency varies from 2 ug (oil dose) to 27 ug (vegetable) carotene to 1 retinol equivalent and the equivalency is matrix dependent, it is necessary to know what the vitamin A equivalency of golden rice beta-carotene is. The determination of the absorption and conversion of golden rice beta-carotene is of importance for designing food programs in many rice-eating regions of the world, where vitamin A deficiency is common.

To evaluate the absorption and intestinal conversion of rice beta-carotene after an acute dose of golden rice, an intrinsically labeled Golden Rice with a labeled reference dose of vitamin A are used. We propose to conduct a pilot study on the US adults with normal vitamin A status (n = 15).

The specific aims of this pilot study are:

1. To determine ß-carotene response kinetics following a meal of golden rice with 0, 5, or 10 g fat (butter);
2. To determine retinol kinetics from the golden rice and from the labeled vitamin A dose;
3. To determine vitamin A value of golden rice ß-carotene in adults with normal vitamin A status. The determination of the absorption and conversion of golden rice ß-carotene is of importance for designing food programs in many rice-eating regions of the world, where vitamin A deficiency is common.

Eligibility criteria: Inclusion Criteria:

* healthy health

Exclusion Criteria:

* GI track problems

Primary outcomes:
measure: The enrichment of labeled golden rice β-carotene and its conversion to labeled retinol in serum samples after the golden rice meal with 0, 5, or 10 g fat (butter) as compared to the reference dose of vitamin A that is labeled differently.
timeFrame: 33 days
Secondary outcomes:
Other outcomes:
Locations:
city: Boston
country: United States
facility: USDA Human Nutrition Research Center on Aging at Tufts Uni
state: Massachusetts
Study officials:
affiliation: Tufts University
name: Guangwen Tang, Ph. D
role: PRINCIPAL_INVESTIGATOR
References:
citation: Tang G, Qin J, Dolnikowski GG, Russell RM, Grusak MA. Golden Rice is an effective source of vitamin A. Am J Clin Nutr. 2009 Jun;89(6):1776-83. doi: 10.3945/ajcn.2008.27119. Epub 2009 Apr 15.