Non-celiac gluten sensitivity not yet universally adopted. For people on a gluten-free diet who are unable to perform an oral gluten challenge, an alternative to identify possible celiac disease is an in vitro gliadin challenge of small bowel biopsies; this test is only available at selected specialized tertiary-care centers. After exclusion of celiac disease and wheat allergy, the subsequent step for diagnosis and treatment of NCGS is to start a strict gluten-free diet (GFD) to assess if symptoms improve or resolve completely. This may occur within days to weeks of starting a GFD, but improvement may also be due to a non-specific, placebo
Wheat gluten (food) among adherents of Buddhism. The oldest reference to wheat gluten appears in the "Qimin Yaoshu", a Chinese agricultural encyclopedia written by Jia Sixie in 535. The encyclopedia mentions noodles prepared from wheat gluten called "bo duo". Wheat gluten was known as "mian jin" by the Song dynasty (960–1279). Wheat gluten arrived in the West by the 18th century. "De Frumento", an Italian treatise on wheat from 1745, describes the process of washing wheat flour dough in order to extract the gluten. John Imison wrote an English-language definition of wheat gluten in his "Elements of Science and Art" published in 1803.