Scope: Immunoglobulin E-mediated food allergies (IgE-FA) are characterized by an ever-increasing prevalence, currently reaching up to 10.4% of children in the European Union. Metabolomics has the potential to provide a deeper understanding of the pathogenic mechanisms behind IgE-FA. Methods and Results: In this work, literature is systematically searched using Web of Science, PubMed, Scopus, and Embase, from January 2010 until May 2021, including human and animal metabolomic studies on multiple biofluids (urine, blood, feces). In total, 15 studies on IgE-FA are retained and a dataset of 277 potential biomarkers is compiled for in-depth pathway mapping. Decreased indoleamine 2,3-dioxygenase-1 (IDO-1) activity is hypothesized due to altered plasma levels of tryptophan and its metabolites in IgE-FA children. In feces of children prior to IgE-FA, aberrant metabolization of sphingolipids and histidine is noted. Decreased fecal levels of (branched) short chain fatty acids ((B)SCFAs) compel a shift towards aerobic glycolysis and suggest dysbiosis, associated with an immune system shift towards T-helper 2 (Th2) responses. During animal anaphylaxis, a similar switch towards glycolysis is observed, combined with increased ketogenic pathways. Additionally, altered histidine, purine, pyrimidine, and lipid pathways are observed. Conclusion: To conclude, this work confirms the unprecedented opportunities of metabolomics and supports the in-depth pathophysiological qualification in the quest towards improved diagnostic and prognostic biomarkers for IgE-FA.

Mol. Nutr. Food Res. 2021, 65, 202100536 DOI: https://doi.org/10.1002/mnfr.202100536 IgE‐mediated food allergies (IgE‐FA) are considered a growing epidemic. Its pathogenic mechanisms remain however largely unknown. The authors performed a literature search followed by in‐depth pathway mapping of IgE‐FA in children, and revealed a shift in energy metabolism, next to aberrant metabolization of bile acids, lipids, nucleotides, fecal SCFAs and amino acids. As such, this work confirmed the unprecedented opportunities of metabolomics while offering a solid basis for future FA research. This is reported by Lynn Vanhaecke and co‐workers in article number 2100536.