BackgroundYellow-fleshed potatoes biofortified with iron have been developed through conventional breeding, but the bioavailability of iron is unknown.ObjectivesOur objective was to measure iron absorption from an iron-biofortified yellow-fleshed potato clone in comparison with a nonbiofortified yellow-fleshed potato variety.MethodsWe conducted a single-blinded, randomized, crossover, multiple-meal intervention study. Women (n= 28; mean ± SD plasma ferritin 21.3 ± 3.3 μg/L) consumed 10 meals (460 g) of both potatoes, each meal extrinsically labeled with either58Fe sulfate (biofortified) or57Fe sulfate (nonfortified), on consecutive days. Iron absorption was estimated from iron isotopic composition in erythrocytes 14 d after administration of the final meal.ResultsMean ± SD iron, phytic acid, and ascorbic acid concentrations in iron-biofortified and the nonfortified potato meals (mg/per 100 mg) were 0.63 ± 0.01 and 0.31 ± 0.01, 39.34 ± 3.04 and 3.10 ± 1.72, and 7.65 ± 0.34 and 3.74 ± 0.39, respectively (P< 0.01), whereas chlorogenic acid concentrations were 15.14 ± 1.72 and 22.52 ± 3.98, respectively (P< 0.05). Geometric mean (95% CI) fractional iron absorption from the iron-biofortified clone and the nonbiofortified variety were 12.1% (10.3%–14.2%) and 16.6% (14.0%–19.6%), respectively (P< 0.001). Total iron absorption from the iron-biofortified clone and the nonbiofortified variety were 0.35 mg (0.30–0.41 mg) and 0.24 mg (0.20–0.28 mg) per 460 g meal, respectively (P< 0.001).ConclusionsTIA from iron-biofortified potato meals was 45.8% higher than that from nonbiofortified potato meals, suggesting that iron biofortification of potatoes through conventional breeding is a promising approach to improve iron intake in iron-deficient women.The study was registered atwww.clinicaltrials.govas Identifier number NCT05154500.