Increasing evidence suggests that high consumption of ultra-processed foods (UPF) is associated with an increase in noncommunicable diseases, overweight, and obesity. This review aimed to verify the association of UPF with inflammatory diseases, especially allergic diseases. To identify relevant articles, an extensive literature search was conducted using the two most important search sites - PubMed and Google Scholar. Specific Medical Subject Headings (MeSHes) such as "food additives and health," "food additives and immune system," and "food additives and diseases" were used to conduct an advanced search. Emulsifiers have been, particularly, implicated in disrupting intestinal barrier function, modifying gut microbiota, and promoting inflammation, which may contribute to the development of food allergies and inflammatory diseases. While food additives serve various functions in the food industry, concerns regarding their impact on health, particularly in systemic autoimmune and metabolic conditions, have been raised. Common additives have been associated with allergic reactions, intolerances, and sensitivities.