Both celiac disease and Crohn's are autoimmune diseases that primarily affect the intestines. In an autoimmune disease, the body's immune system over-reacts and attacks cells in the body as if they were foreign objects, such as bacteria or other toxins.

Celiac and Crohn's produce similar symptoms: most often intermittent diarrhea, abdominal pain and bloating. Crohn's disease may affect all parts of the digestive system, but predominantly occurs in the intestines, in particular the terminal ileum and proximal colon. Celiac disease destroys the villi in the intestine. Villi are finger-like projections on the surface of the small intestines. They increase the surface area roughly 10 times, which increases our ability to absorb digested food.

There is a high prevalence of celiac disease in people who have inflammatory bowel disease, and both often result in malabsorption. With Celiac disease, malabsorption is due to gluten-induced damage to the small intestine. The primary treatment is a strict gluten-free diet. Gluten is a sticky protein that is found primarily in wheat. It's the substance that binds together wheat and water in dough. In people who have Celiac disease, the body has an improper immune system response to gluten, and must follow a gluten-free diet.

The exact relationship between Crohn's and celiac disease is not certain. However, researchers do have a hypothesis.

The gastrointestinal system is a complex eco-system, teaming with friendly bacteria and other organisms. In a healthy person, the body maintains the right balance between antigens (substances that stimulate production of antibodies and protect us from toxins) and an immune response. 

In both Crohn's and Celiac, the wall of the gut becomes increasingly permeable, due to disease-related damage, allowing substances to pass through the intestinal wall. Researchers suspect that this increased permeability in Crohn's patients exposes bacteria that trigger a specific immune reaction, which in turn causes the body to develop lesions indicative of celiac disease. They also find pro-inflammatory proteins called cytokines in people with these diseases.

Some experts recommend all patients who have Crohn's disease also begin a gluten-free diet. Adhering to a gluten-free diet is difficult, especially in our society in which we eat many corn and wheat products.

You'll find gluten in many foods; even some you might not suspect.

If you have Crohn's disease, ask your physician about the likelihood you might also develop Celiac disease, and whether following a gluten-free diet makes sense. If it does, work with a qualified nutrition professional who can help you develop a customized diet.


Celiac Disease Prevalence High in Patients with Crohn's Disease

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