The increased finding of patients with oral signs and symptoms, probably due to allergic reactions to food, seems to require clarifying on the role and variants of food allergy in oral medicine. Over the last 20 years, studies in general on food allergies, have investigated related signs and symptoms as well as allergens and mediators involved in the mechanisms of reaction on a considerable scale. So, it has been possible to divide adverse reactions to food into toxic and non-toxic (allergies or non-immunologic intolerance). In particular, the allergic reactions have been divided into IgE-mediated, the most frequent, and non IgE-mediated, the latter along with mechanisms of cellular-mediated hypersensitivity or immuno-complex, until now, not so well identified. In the present review, the authors investigated the adverse reactions to food involving the oral mucosa, and illustrated the several pictures and clinical variants reported in the literature, in relation to the different allergens and mechanisms. The evidence of the most frequent involvement of IgE-mediated components in food oral allergy, should represent a diagnostic guideline in ruling-out some oral mucosal lesions and in planning prevention and therapy protocols. Finally, investigating the role of the IgE-mediated component in patients with unspecified burning oral symptoms could be interesting and provides useful information.