Summary: Food allergy (FA) is a repetitive adverse reaction to a given food due to a specific immunologic response. Based on the underlying immunologic mechanisms, it is classified into IgE-mediated allergy, non-IgE-mediated allergy, and mixed forms. Non-IgE-mediated FA includes food protein-induced enterocolitis syndrome (FPIES), food protein-induced proctocolitis (FPIAP), and food protein-induced enteropathy (FPE). Due to a different pathomechanism compared to IgE-mediated FA, the diagnosis of non-IgE-mediated FA is challenging and relies mainly on clinical data. The diagnosis is based on a medical history that identifies the occurrence of repetitive, characteristic symptoms after consuming a specific food. Confirmation of the diagnosis is established by the resolution of clinical symptoms with the introduction of an elimination diet and their recurrence upon reintroduction of the specific food into the diet. Therefore, oral food challenge (OFC) remains the gold standard for confirming the diagnosis of non-IgE-mediated FA. However, this procedure is invasive and requires financial resources as well as specialized personnel to conduct it. Consequently, there are ongoing efforts to explore alternative methods for diagnosing non-IgE-mediated FA, and one of them involves the use of various biomarkers that could provide a non-invasive and faster diagnosis for Non-IgE-mediated FA.