What is celiac disease?

Celiac disease is a chronic inflammatory disorder of the small intestine in genetically susceptible individuals. It is triggered by ingesting certain proteins, commonly referred to as "gluten" which is naturally present in some cereal grains - specifically wheat, barley, rye, kamut, spelt, and triticale.
A part of the protein gluten in these specific grains combines with an immune system molecule (normally DQ2 or DQ8, thought the process is not 100% understood), producing an immune reaction that attacks the intestine itself, and can lead to an extremely large variety of symptoms, including pain, diarrhea, fatigue, and poor absorption of nutrients. Over time, damage to the intestine can lead to severe infections, osteoporosis, internal bleeding, and cancer of the intestine.

Sufferers of Celical (or Coeliac) disease have to be extremely careful what they eat, as the majority of prepared and restaurant food contains or is contaminated with the specific glutens that cause the reaction. A miniscule, invisible amount of wheat flour can trigger the process.
The types of food and levels of contamination are widely understood, and many sufferers simply avoid all food prepared by others permanently.
Approximately 1.3% of the population suffers from Celiac disease, up to 5% may be intolerant to gluten in a less serious way.
Celiac disease is a common illness for which there is no cure, and affects people of all ages. With this disease, you cannot eat wheat, rye, barley, and gluten, among other foods. This disease affects the villi in the intestines. This may not show symptoms in some people, but may in others, such as diarrhea, constipation, sickness, ulcers of the mouth, and stomach ache.
it is an alergy to different kinds of grains.