Understanding Celiac Disease

Celiac disease is a genetic immune-mediated disorder. This means that it is a condition that is passed down in families where the immune system attacks a healthy part of the body by mistake. Grains, such as wheat, rye and barley, contain specific storage proteins that are sticky and elastic and allow dough and bread to rise. These proteins are specifically known as gliadin when found in wheat, secalin in rye, and hordein in barley. In celiac disease, the storage proteins in these grains trigger the body to cause damage to the small intestine. All forms of these grains must be avoided. The only treatment for celiac disease is to follow a gluten-free diet for life.1 Visit the Simple Start to the Gluten-Free Diet section to learn which grains to choose and which to avoid.

Prevalence of Celiac Disease

Celiac disease (CD) may affect as many as 1.4% of North America’s population. An accurate number is unknown because many cases remain undiagnosed.2 It is most commonly diagnosed in people with North American or European descent. It is also found in people from the Middle East, North Africa, Turkey, India and around the world. Women are slightly more likely to be affected by CD.2 Although the most common age at diagnosis in the US is about 40 years, CD may be diagnosed at any age and most people probably develop CD at a younger age.3,4

Common Questions About Celiac Disease

Whether you suspect having a gluten intolerance or have been recently diagnosed with celiac disease, it is important to understand how celiac disease can affect your health. The following questions and answers provide valuable information about celiac disease symptoms and diagnosis.

Take-Home Messages

  • The symptoms listed above are not unique to celiac disease and can occur with other disorders and diseases.

  • With more widespread use of antibody testing and small intestinal biopsies to diagnose CD, several categories of CD have now emerged. These include classical disease, non-classical presentations, subclinical and potential forms of the disease. Knowing which form of CD you have is important information for you and your doctor.

  • The non-classical form of CD is currently the most common or typical presentation of CD. For this reason, both patients and doctors need to be on the close look-out for the wide variety of symptoms and to screen for CD so that it can be found as early as possible.

  • If you or your doctor recognizes your symptoms in the list above, consider getting tested for CD.

  • If you suspect CD, do not start a gluten-free diet on your own until you have met with a gastroenterologist and have been evaluated.

  • Early diagnosis and effective treatment of celiac disease greatly improves your health outcomes and reduces the risks of complications from untreated disease.

  • Non-celiac gluten sensitivity (NCGS) is an increasingly seen clinical condition with gastrointestinal symptoms like those found in CD. It is important to screen for CD and/or a wheat or gluten allergy before starting a gluten-free diet, as NCGS is a diagnosis of exclusion.


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Revision Date: March 1, 2022
Author: Amelie Therrien MD
Editors: Melinda Dennis, MS, RDN, LD, and Daniel Leffler, MD, MS