Iron bioaccessibility in raw and cooked foods in vitro using fecal inocula from children and adults

Úrsula García-Conde; Miguel Navarro-Moreno; Konstantinos Douros; Miguel Navarro-Alarcón; José Ángel Rufián-Henares; Silvia Pastoriza

doi:10.1016/j.fochx.2025.102764

Iron bioaccessibility in raw and cooked foods in vitro using fecal inocula from children and adults

Food Chem X. 2025 Jul 9:29:102764. doi: 10.1016/j.fochx.2025.102764. eCollection 2025 Jul.

Authors

Úrsula García-Conde¹, Miguel Navarro-Moreno¹, Konstantinos Douros², Miguel Navarro-Alarcón¹, José Ángel Rufián-Henares^{1

3}, Silvia Pastoriza¹

Affiliations

¹ Department of Nutrition and Food Science, Faculty of Pharmacy, Biomedical Research Center, University of Granada, 18071 Granada, Spain.
² Pediatric Allergy and Respiratory Unit, 3rd Department of Pediatrics, "Attikon" University Hospital, National and Kapodistrian University of Athens, School of Medicine, 11527 Athens, Greece.
³ Biosanitary Research Institute (IBS), University of Granada, Granada, Spain.

Abstract

Iron (Fe) is essential for human health but may induce dysbiosis and inflammation when unabsorbed. This study assessed the impact of culinary techniques on Fe bioaccessibility (FeBA) using an in vitro digestion/fermentation model with fecal inocula from children and adults. FeBA in the small intestine was significantly lower in plant-based (12.2 ± 9.91 %; 1.05 ± 0.85 mg/kg) than in animal-based foods (16.8 ± 11.7 %; 1.25 ± 0.86 mg/kg) (p < 0.0001). Cooking methods such as grilling, frying, and roasting enhanced FeBA in plant foods, likely due to Maillard reaction products. In allergic children, FeBA in the large intestine (1.77 ± 2.07 %; 0.13 ± 0.17 mg/kg) was significantly higher than in healthy, celiac, and obese children (p < 0.0001), possibly linked to colonic dyshomeostasis, oxidation, and inflammation. Overall, FeBA depends on food type, preparation method, and gut health status, and is mainly driven by small intestinal absorption.

Keywords: Fe bioaccessibility; Healthy/sick children; Plant/animal foods; Raw/cooked foods.