β-Carotene in biofortified maize has good bioavailability as a plant source of vitamin A.

High β‐carotene maize is being developed through plant breeding as a sustainable agronomic approach to alleviate vitamin A deficiency in Africa. Our objective was to quantify the vitamin A equivalence of high β‐carotene maize based on ingestion of a single realistic serving of maize porridge. Women (n = 6) each consumed in random order 3 maize porridges (250 g each) containing 62.5 g maize flour: 1) high β‐carotene maize porridge (526.8 μg β‐carotene); 2) white maize porridge with β‐carotene reference dose (535.7 μg added β‐carotene); 3) white maize porridge with vitamin A reference dose (285.6 μg added retinol). Blood samples were collected over 9 h. Retinyl palmitate was analyzed in triacylglycerol‐rich lipoprotein fractions by HPLC with coulometric array electrochemical detection. Areas under the curve (AUC) for retinyl palmitate were 9.46 ± 1.41 nmol·h/L, 34.06 ± 4.31 nmol·h/L, and 32.32 ± 5.05 nmol·h/L after ingestion of high β‐carotene maize porridge, white maize porridge with β‐carotene reference dose, and white maize porridge with vitamin A reference dose, respectively. The vitamin A equivalence of the β‐carotene in high β‐carotene maize was 6.90 ± 1.53 to 1 (by wt); the vitamin A equivalence of the β‐carotene reference dose (2.11 ± 0.59 to 1) approximated that established by the U.S. Institute of Medicine. High β‐carotene maize is a bioavailable source of vitamin A. Supported by USAID/CIAT and HarvestPlus.