A decade ago, celiac disease was considered extremely rare outside Europe and was largely ignored by healthcare professionals. However, in just 10 years, it has become a global health concern. The rise in gluten-free diets (GFDs) has led to a growing market for gluten-free products, with global sales reaching $2.5 billion in 2010. This trend is supported by the emergence of other gluten-related conditions, such as wheat allergy (WA), gluten sensitivity (GS), and autoimmune disorders like dermatitis herpetiformis (DH) and gluten ataxia (GA). This review summarizes the current understanding of these conditions, their pathogenic, clinical, and epidemiological differences, and proposes new nomenclature and classifications. Wheat, rice, and maize are the most widely consumed grains globally. Gluten, a complex protein in wheat, is toxic in some individuals, leading to conditions like celiac disease (CD) and wheat allergy. CD is an autoimmune disorder triggered by gluten in genetically predisposed individuals, characterized by damage to the small intestine. DH is a skin manifestation of CD, with IgA deposits in the skin. GA is an autoimmune disorder affecting the cerebellum, leading to ataxia. GS is a condition distinct from CD, with no autoimmune markers and normal small intestine damage. The classification of gluten-related disorders includes WA, CD, DH, GA, and GS. Diagnosis of CD involves serological tests and intestinal biopsy, while GS is diagnosed by exclusion. The proposed algorithm differentiates these conditions based on clinical, biological, genetic, and histological data. Treatment for all conditions involves a GFD, though CD requires lifelong strict adherence. GS and other conditions have unclear natural histories, requiring further research. The prevalence of CD is increasing, particularly in developing countries due to Westernization of diets. Genetic factors, including HLA-DQ2 and HLA-DQ8, play a significant role in CD susceptibility. GS is more common than CD, with a higher prevalence in the general population. The rise in gluten-free diets is partly due to the perception of GFDs as beneficial for health, even in the absence of a confirmed diagnosis. This review highlights the need for a unified classification and nomenclature of gluten-related disorders to improve diagnosis and treatment. The growing market for gluten-free products underscores the importance of understanding the spectrum of gluten-related conditions and their underlying mechanisms.A decade ago, celiac disease was considered extremely rare outside Europe and was largely ignored by healthcare professionals. However, in just 10 years, it has become a global health concern. The rise in gluten-free diets (GFDs) has led to a growing market for gluten-free products, with global sales reaching $2.5 billion in 2010. This trend is supported by the emergence of other gluten-related conditions, such as wheat allergy (WA), gluten sensitivity (GS), and autoimmune disorders like dermatitis herpetiformis (DH) and gluten ataxia (GA). This review summarizes the current understanding of these conditions, their pathogenic, clinical, and epidemiological differences, and proposes new nomenclature and classifications. Wheat, rice, and maize are the most widely consumed grains globally. Gluten, a complex protein in wheat, is toxic in some individuals, leading to conditions like celiac disease (CD) and wheat allergy. CD is an autoimmune disorder triggered by gluten in genetically predisposed individuals, characterized by damage to the small intestine. DH is a skin manifestation of CD, with IgA deposits in the skin. GA is an autoimmune disorder affecting the cerebellum, leading to ataxia. GS is a condition distinct from CD, with no autoimmune markers and normal small intestine damage. The classification of gluten-related disorders includes WA, CD, DH, GA, and GS. Diagnosis of CD involves serological tests and intestinal biopsy, while GS is diagnosed by exclusion. The proposed algorithm differentiates these conditions based on clinical, biological, genetic, and histological data. Treatment for all conditions involves a GFD, though CD requires lifelong strict adherence. GS and other conditions have unclear natural histories, requiring further research. The prevalence of CD is increasing, particularly in developing countries due to Westernization of diets. Genetic factors, including HLA-DQ2 and HLA-DQ8, play a significant role in CD susceptibility. GS is more common than CD, with a higher prevalence in the general population. The rise in gluten-free diets is partly due to the perception of GFDs as beneficial for health, even in the absence of a confirmed diagnosis. This review highlights the need for a unified classification and nomenclature of gluten-related disorders to improve diagnosis and treatment. The growing market for gluten-free products underscores the importance of understanding the spectrum of gluten-related conditions and their underlying mechanisms.