Gluten is a family of proteins found in wheat, barley, and rye.
Glutenin and gliadin are the two primary proteins found in these grains and they play a role in giving gluten-containing foods like dough its elasticity and bread its spongy texture.
On its own, gluten is not a harmful substance. In fact, most people tolerate gluten perfectly well. The problem occurs when the body mistakenly recognizes gluten as a foreign substance and launches a systemic attack against it. Celiac disease, for example, is an autoimmune condition in which the body recognizes gluten as a foreign invader and acts out against it. In the process, however, healthy cells lining the walls of the small intestine sustain damage which inhibits the body’s ability to properly absorb nutrients from food.
A wheat allergy is somewhat different because it can be triggered by proteins other than gluten. The body’s response, however, is very similar – it launches an
attack against the foreign substance by producing immunoglobulin E (IgE) antibodies while other tissues in the body send out chemical messengers alerting the body to the threat. The resulting reaction causes side effects such as itchy rash, nausea, abdominal pain, swollen tongue or lips, difficulty breathing, and anaphylaxis.
Non-celiac gluten-sensitivity. This term is not clearly defined by the medical community and there is no clear diagnosis or set of symptoms. Gluten intolerance is thought to be a more severe form of this sensitivity and may result in immune system activity and the resulting side effects, though not to the same degree of severity as an allergy or autoimmune disorder. Anyone with celiac disease, gluten/wheat allergy, or gluten sensitivity/intolerance could benefit from switching to a gluten-free diet.