12/01/2009 05:12 am ET | Updated Nov 17, 2011

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Celiac Disease: A Diagnosis Often Missed

There's a disease that American doctors are absolutely terrible at diagnosing. It's estimated that three million Americans have celiac disease and only a small percentage of them know it. In celiac disease, a component of wheat, rye, and barley called gluten sets off an immune reaction that attacks the intestine and can affect the entire body.

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Patients are unable to properly absorb essential nutrients because the absorptive fingers (villi) in the small intestine have been damaged or destroyed. Doctors usually miss the diagnosis because they don't realize how variable the disease can be. Here is a list of associated symptoms and problems:

Diarrhea, abdominal pain, bloating, gas, distention, weight loss, constipation, irritable bowel syndrome, failure to thrive in infancy, vomiting, short stature, iron deficiency with or without anemia, poor performance in school, delayed puberty, infertility, recurrent miscarriage, osteoporosis, vitamin deficiencies, fatigue, tooth discoloration and dental enamel defects, skin disorders, elevated liver enzymes, Down syndrome, Sjogren's syndrome, aphthous ulcers (canker sores), arthritis, depression, nerve and balance problems (peripheral neuropathy and cerebellar ataxia), irritability in children, seizures, and migraines. Patients with other autoimmune diseases such as type 1 diabetes and thyroiditis are at increased risk for celiac disease.

Click here for the National Institute of Health's information on celiac disease.

There appears to be a slight increase in the risk of lymphomas and gastrointestinal cancers that,