Oat vary among oat varieties. Also, oats products are frequently cross-contaminated with other gluten-containing cereals during grain harvesting, transport, storage or processing. Pure oats contain less than 20 parts per million of gluten from wheat, barley, rye, or any of their hybrids. Use of pure oats in a gluten-free diet offers improved nutritional value from the rich content of oat protein, vitamins, minerals, fiber, and lipids, but remains controversial because a small proportion of people with celiac disease react to pure oats. Some cultivars of pure oat could be a safe part of a gluten-free diet, requiring knowledge of the oat
Gluten diet and a self-diagnosis of gluten sensitivity. People with NCGS may develop gastrointestinal symptoms, which resemble those of irritable bowel syndrome or wheat allergy, or a wide variety of non-gastrointestinal symptoms, such as headache, chronic fatigue, fibromyalgia, atopic diseases, allergies, neurological diseases, or psychiatric disorders, among others. Besides gluten, additional components present in wheat, rye, barley, oats, and their derivatives, including other proteins called ATIs and short-chain carbohydrates known as FODMAPs, may cause NCGS symptoms. The effects of FODMAPs are only limited to gastrointestinal mild discomfort. ATIs may cause toll-like receptor 4 (TLR4)-mediated intestinal inflammation in humans. People can also