Gluten is a protein naturally found in cereals, such as wheat, barley, and rye and therefore in products made of those cereals (e.g., bread, pasta, biscuits). Gluten is responsible for creating an elastic and chewy texture in food products due to its viscoelastic and adhesive properties.

Coeliac disease is a serious life-long autoimmune disorder occurring in genetically predisposed people where the consumption of gluten triggers an immune response that attacks the small intestine. This adverse immune response damages the micro villi lining in the small intestine, resulting in malabsorption of nutrients from food.

Coeliac disease can develop at any age after people start eating gluten. Without adequate diagnosis and treatment, coeliac patients risk the development of other conditions such as osteoporosis, diabetes and intestinal cancer.

Wheat allergy is sometimes confused with coeliac disease as it also triggers a defence reaction of the body towards various proteins in wheat, including gluten. However, while with coeliac disease all types of gluten-containing cereals must be strictly avoided, with wheat allergy it is necessary to primarily avoid wheat. Unlike celiac disease, wheat allergy can be outgrown.

Non-coeliac gluten sensitivity is not an autoimmune disorder but a condition that occurs when coeliac disease and wheat allergy is medically ruled out, but the consumption of gluten-containing foods causes intestinal and extra-intestinal symptoms. This condition is still poorly understood to date.