<unk>  (NCGS) or<unk><unk>  is "a clinical entity induced by the ingestion of<unk>  leading to intestinal and/or extraintestinal symptoms that improve once the<unk> -containing foodstuff is removed from the diet, and<unk>  disease and wheat allergy have been excluded". NCGS is included in the spectrum of<unk> -related disorders. The definition and diagnostic criteria of<unk>  were debated and established by three consensus conferences. However, as of 2019, there remained much debate in the scientific community as to whether or not NCGS was a distinct clinical disorder. The pathogenesis of NCGS is not well understood, but the activation of the innate immune system, the direct cytotoxic effects of<unk>  and probably other wheat components, are implicated. There is evidence that not only gliadin (the main cytotoxic antigen of<unk> , but also other proteins named ATIs which are present in<unk> -containing cereals (wheat, rye, barley, and their derivatives) may have a role in the development of symptoms. ATIs are potent activators of the innate immune system. FODMAPs, especially fructans, are present in small amounts in<unk> -containing grains and have been identified as a possible cause of some gastrointestinal symptoms in NCGS patients. As of 2019, reviews have concluded that although FODMAPs may play a role in NCGS, they explain only certain gastrointestinal symptoms, such as bloating, but not the extra-digestive symptoms that people with NCGS may develop, such as neurological disorders, fibromyalgia, psychological disturbances, and dermatitis. For these reasons, NCGS is a controversial clinical condition and some authors still question it. It has been suggested that "non-celiac wheat<unk> " is a more appropriate term, without forgetting that other<unk> -containing cereals are implicated in the development of symptoms. NCGS is the most common syndrome of<unk> -related disorders with prevalence rates between 0.5%–13% in the general population. As no biomarker for diagnosing this condition is available, its diagnosis is made by exclusion of other<unk> -related disorders such as<unk>  disease and wheat allergy. Many people have not been diagnosed following strict criteria, and there is a "fad component" to the recent rise in popularity of the<unk> -free diet, leading to debate surrounding the evidence for this condition and its relationship to<unk>  disease and irritable bowel syndrome. People with NCGS are often unrecognized by specialists and lack adequate medical care and treatment. They often have a long history of health complaints and unsuccessful consultations with physicians, and thus many resort to a<unk> -free diet and a self-diagnosis of<unk><unk> .
Non-celiac gluten sensitivity
Hereditary diffuse gastric cancer
Intestinal neuronal dysplasia
Autoimmune gastrointestinal dysmotility
Tropical sprue
Lysinuric protein intolerance
Exocrine pancreatic insufficiency
Foreign body in alimentary tract