Digesting the Facts About Celiac Disease

Reported by Dr. Ana Nobis for ABC News Health

Gluten, the protein found in wheat, barley and rye, causes a lot of trouble for a lot of people. Nearly 2 million Americans suffer from celiac disease, a condition where the inability to properly digest gluten leads to chronic gastrointestinal symptoms such as bloating, gas and diarrhea.

On Tuesday, Dr. Richard Besser, chief health and medical correspondent for ABC News, hosted a Twitter chat on this common, yet commonly misdiagnosed disease to clear up any myths and misconceptions about celiac, gluten intolerance and gluten-free eating. Dr. Besser was joined by top experts from around the country.

Click here for the full chat transcript. Read on for the highlights.

What causes celiac disease?

Celiac disease occurs when an individual's own immune system overreacts to gluten. The inflammatory response damages the delicate lining of the small intestine, where most nutrients are absorbed.

Who gets celiac disease?

About 1 percent of the population has celiac disease, according to National Institutes of Health statistics.

Certain genes place individuals at increased risk for celiac disease, but not everyone who has those genes will get the disease. And genes are only half the story: The disease only develops when someone who is genetically predisposed to celiac eats gluten.

Women are more likely to suffer from celiac. So are people with type 1 diabetes, Down syndrome, Turner syndrome, autoimmune thyroid disease and Sjogren's syndrome. It's more common in Caucasians than other ethnicities and anyone with a close relative who has the disease. Both children and adults can be celiac.

An unknown percentage of people may not have full-blown celiac but struggle with gluten sensitivities or gluten intolerance.

What are the symptoms of celiac disease?

There are three forms of celiac disease: classic, atypical and asymptomatic.

People who struggle with a classic form of the disease often experience diarrhea and weight loss. People with the atypical form experience the digestive complaints along with symptoms like anemia, fatigue, headaches, joint pain, osteoporosis, numbness or tingling in the hands or feet, or an itchy skin condition known as dermatitis herpetiformis.

Asymptomatic disease-as the name implies-is often detected accidentally during medical tests run for some other medical problem; however these patients frequently notice improvements in symptoms such as fatigue after adopting a gluten-free diet.

Who should get tested and how is it diagnosed?

Individuals with autoimmune conditions associated with celiac disease should get screened. So should people with first degree relatives who have celiac. Initial screening involves a simple blood test to check for specific antibodies produced in celiacs after they've consumed gluten. The diagnosis is confirmed by an endoscopy and biopsy of the small intestine.

There's no reliable test for gluten sensitivity or intolerance. A doctor often makes this diagnosis when other medical conditions are ruled out.

How do you treat celiac disease?

Currently the only way to treat celiac disease is to eliminate gluten from the diet. This means avoiding any products containing wheat, barley, rye, and triticale (a cross between wheat and rye). Oats don't contain gluten but some oat products can be contaminated with wheat. Rice, corn, and soy are naturally gluten-free. Many celiacs find it helpful to meet with a registered dietitian and nutritionist to help plan a diet that's gluten-free and healthy.