β-Carotene in Golden Rice is as good as β-carotene in oil at providing vitamin A to children

Abstract

Background: Golden Rice (GR) has been genetically engineered to be rich in β-carotene for use as a source of vitamin A.

Objective: The objective was to compare the vitamin A value of β-carotene in GR and in spinach with that of pure β-carotene in oil when consumed by children.

Design: Children (n = 68; age 6-8 y) were randomly assigned to consume GR or spinach (both grown in a nutrient solution containing 23 atom% ²H₂O) or [²H₈]β-carotene in an oil capsule. The GR and spinach β-carotene were enriched with deuterium (²H) with the highest abundance molecular mass (M) at M(β-C)+²H₁₀. [¹³C₁₀]Retinyl acetate in an oil capsule was administered as a reference dose. Serum samples collected from subjects were analyzed by using gas chromatography electron-capture negative chemical ionization mass spectrometry for the enrichments of labeled retinol: M(retinol)+4 (from [²H₈]β-carotene in oil), M(retinol)+5 (from GR or spinach [²H₁₀]β-carotene), and M(retinol)+10 (from [¹³C₁₀]retinyl acetate).

Results: Using the response to the dose of [¹³C₁₀]retinyl acetate (0.5 mg) as a reference, our results (with the use of AUC of molar enrichment at days 1, 3, 7, 14, and 21 after the labeled doses) showed that the conversions of pure β-carotene (0.5 mg), GR β-carotene (0.6 mg), and spinach β-carotene (1.4 mg) to retinol were 2.0, 2.3, and 7.5 to 1 by weight, respectively.

Conclusions: The β-carotene in GR is as effective as pure β-carotene in oil and better than that in spinach at providing vitamin A to children. A bowl of ~100 to 150 g cooked GR (50 g dry weight) can provide ~60% of the Chinese Recommended Nutrient Intake of vitamin A for 6-8-y-old children.

Trial registration: ClinicalTrials.gov NCT00680212.

Figures

FIGURE 1.

The enrichment profiles of β-carotene in chemically synthesized β-carotene and of the plant foods Golden Rice and spinach as analyzed by using liquid chromatography–atmospheric pressure mass spectrometry. β-C, β-carotene; M, molecular mass.

FIGURE 2.

Diagram of the study timeline. β-C, β-carotene.

FIGURE 3.

Mean enrichment (±SD) of serum retinols by treatment and time. Left panel: response to β-carotene in oil capsule (0.5 mg β-carotene) and [13C10]retinyl acetate (0.5 mg); middle panel: response to Golden Rice (0.6 mg β-carotene) and [13C10]retinyl acetate (0.5 mg); and right panel: response to spinach (1.4 mg β-carotene) and [13C10]retinyl acetate (0.5 mg). The number of children providing blood at the 5 time points is presented in the text box under the enrichment response graph of each group. β-C, β-carotene.