Summary: Food hypersensitivity represents a heterogeneous group of reactions that include both immune-mediated food allergies and non-immunological adverse reactions to foods. In recent years, an increasing number of patients report symptoms after food consumption, which constitutes a significant diagnostic challenge in clinical practice. The aim of this article is to present current data on the epidemiology of food hypersensitivity and food allergy, discuss the key differences between food allergy and food intolerance, and review the main pathophysiological mechanisms and clinical manifestations of IgE-mediated and non-IgE-mediated reactions. Particular attention is given to the diagnosis of IgE-mediated food allergy, in which a carefully conducted clinical history plays a central role, supported by skin prick testing, measurement of allergen-specific IgE antibodies, and, in selected cases, oral food challenge tests. The article also discusses the role of component-resolved diagnostics, cross-reactivity between aeroallergens and food allergens, and less common conditions such as alpha-gal syndrome. Additionally, selected forms of non-IgE-mediated food allergies, including eosinophilic esophagitis and food protein-induced enterocolitis syndrome (FPIES), are presented. Accurate differentiation between types of food hypersensitivity is crucial for appropriate diagnostic management, treatment strategies, and improving patients’ quality of life.