Tolerance to food antigens is essential for body’s sustainable development under constant antigenic load. Specific IgG against food antigens have been extensively studied in the literature over the recent years. The presence of those associated with various disorders and introduction of elimination diets for certain food products result in good treatment outcomes related not only to the gastrointestinal tract. Investigation of the impact of the long-term IgG-mediated hypersensitivity to food antigens associated with the increased blood-brain barrier permeability is also relevant when studying pathogenesis of the central nervous system disorders. However, identification of specific IgG in the generally healthy people having no history of allergy or inflammation currently provides no clear understanding of their nature and functional significance. Specific IgG are of great interest in terms of predicting the development of functional disorders, remission and treatment of disorders, changes in susceptibility to food antigens at certain age. The results of specific IgG studies are equivocal, which confirms the need to study their structure, epitopes capable of activating autoimmune processes considering the combined effects of medication, environmental conditions and social living conditions. The paper provides the analysis of the currently available research focused on studying specific IgG against food antigens. The data on identification of specific IgG in individuals with various disorders are provided, as well as the gender-related and age-related differences in antibody detection, the relationship between the antibody levels and the rate of food product consumption.