Food allergy symptoms can affect a wide range of organs and systems (including the skin, gastrointestinal tract, and eyes) (respiratory, circulatory, and neurological). They are frequently linked. Their severity ranges from moderate to potentially fatal responses, and their onset might be sudden or chronic. In recent years, food allergies have been the subject of several research, position papers, and guidelines. They have developed a method for categorising symptoms as moderate to severe, separating objective from subjective symptoms, and defining their heterogeneity, particular phenotypes, or syndromes (e.g., lipid transfer protein syndrome or pollen food syndrome). Food allergy responses can also be influenced by cofactors. Non-IgE-gastrointestinal food allergy symptoms, such as eosinophilic esophagitis and food-protein-induced enterocolitis syndrome, are also well characterised and described. Improving one’s understanding of food allergy symptoms is critical for accurate diagnosis and a tailored treatment plan.

The variety of food allergies is now more understood because of improved symptom descriptions and comprehension. The next step is to standardise symptom evaluation not only for physicians but also for patients, researchers, and public health stakeholders in order to define food allergy phenotypes, underlying processes, and endotypes.