Biofortified orange maize is as efficacious as a vitamin A supplement in Zambian children even in the presence of high liver reserves of vitamin A: a community-based, randomized placebo-controlled trial123456

Community-based randomized placebo-controlled trial in rural Zambian preschool children. The orange maize arm randomized 46 children and analyzed 44, and the vitamin A arm randomized 47 and analyzed 45.

Children received biofortified orange maize for 90 days, with a daily placebo oil (214 mL) in the orange arm. The comparator active regimen provided preformed vitamin A as retinyl palmitate in oil, 400 mg RAE in 214 mL daily, with white maize during the same 90-day period; both were given orally.

Biofortified orange maize was efficacious as a vitamin A source and increased total body vitamin A reserves to a degree comparable with the vitamin A supplement and greater than placebo. Median changes in total body vitamin A reserves were 13 (219, 44) mmol for placebo, 84 (21, 146) mmol for orange maize, and 98 (24, 171) mmol for vitamin A; orange maize did not differ from vitamin A (P = 0.34), and both were higher than placebo (P = 0.0034). Serum retinol showed no treatment effect (P = 0.16) and did not change, indicating that serum retinol was not sensitive to the intervention effect. Baseline liver reserves were high at 1.04 (0.97, 1.12) mmol/g liver, with 59% >1 mmol/g, yet orange maize still improved vitamin A status.

The active-arm sample sizes were modest and the intervention lasted only 90 days. Serum retinol did not capture the treatment effect, so conclusions relied on isotope dilution measures. Generalizability is limited to rural Zambian preschool children in a controlled feeding context, and safety interpretation is limited because adverse events were not reported in the extracted data.