Zinc bioaccessibility of foodstuffs after in vitro study in children with illnesses

Abstract

Background: Childhood is a life stage particularly sensitive to malnutrition, including obesity, celiac disease, and food allergies. Zn is an essential element in development, metabolism, and the regulation of inflammatory processes and oxidative stress.Objective: Zn bioaccessibility (Zn-BA), an indicator of the fraction of Zn available for intestinal absorption, is commonly evaluated through in vitro digestion models. This study applied a novel in vitro digestion–fermenta-tion method to assess Zn-BA in various raw and cooked foods using fecal inocula from children with gluten-re-lated disorders (GRD-CH), obesity (OB-CH), and allergy/intolerance to cow’s milk protein (AICM-CH).Results: The results showed that Zn bioaccessibility in the large intestine (Zn-BALI) values were significantly lower in these clinical groups compared to healthy children (P < 0.001). Mean Zn-BALI values in the large intestine of all foods in GRD-CH are significantly higher (34.7 ± 28.8%) than those determined in OB-CH (29.6 ± 30.1%) and AICM-CH (26.7 ± 30.4%) (P < 0.001). For allergic children, Zn-BALI in animal foods was significantly lower than in plant foods and in both plant and animal foods in the other children’s groups (P < 0.05). Zn-BALI in animal foods cooked in liquid media (frying/boiling) was significantly higher than when cooked with hot air (roasting/grilling).Conclusion: In children, the studied diseases diminished the Zn-BALI, which could negatively affect their appropriate long-term development. In sick children, the higher Zn-BALI in celiac children is probably related to differences in gut microbiota composition, as well as to different metabolites and ligands obtained by the fermentation processes, a fact that should be addressed in future studies.