Although reports are scarce, a recent article indicated that the early exposure of neonates to elevated leptin and insulin concentrations from the maternal milk of women with obesity could impact the neonates’ metagenomic profiles as high leptin concentrations are inversely correlated with bacterial amino acid, carbohydrate, vitamin, and amino acid metabolism [64]. The gene discussed is LEP; the disease is obesity due to melanocortin 4 receptor deficiency.