Celiac disease is an autoimmune disease that affects an estimated six million people in the United States and Europe.

It damages the lining of the small intestine which interferes with the absorption of nutrients from food.

Here are some questions I received from readers on this topic:

Q: I read your notes in the Houston Celiac newsletter. I notice that you did not list oats as an issue like wheat, barley and rye. You mention oats only as a problem if cross contaminated with wheat. Is this correct? I thought oats contained gluten.

A: Officially, pure oats do not contain gluten — the protein found in wheat, rye and barley that sets off intestinal damage in people with celiac disease.  Oats contain a protein called "avenin" which is somewhat similar in structure to gluten, however. So while most people with celiac disease do just fine with oats (as long as they are not processed alongside wheat, rye and barley), some may not.

Q: Gluten can be present in barley-brewed beer. How could it not be if barley contains gluten?

A: Good eye. Barley does contain gluten but many experts say that only a fraction gets into beer after the brewing process. In the United States, the Food and Drug Administration allows a product to be called "gluten-free" if it contains less than 20 parts per million (ppm). So a barley-brewed beer may contain traces of gluten and still be labeled "gluten-free."

Q: I have a 12 year-old daughter with celiac and she is an athlete who is constantly on the go. Lots of practices and trying to grab a healthy meal before or after practice. Any ideas on quick meals that give her what she needs? We do pasta, chicken, beef, vegetables, fruits. She is a bit on the fussy side.

A: Rice, corn and potatoes are staple carbs for gluten-free athletes. Think rice cakes, rice and potato-based crackers and corn tortilla snacks for on-the-go. Other gluten-free grains to add to the mix include quinoa, amaranth, soy and millet.

Fruit and vegetables (in their natural packages) are gluten-free as are chicken, beef, and fish. Several companies have introduced gluten-free snack chips made with apples, sweet potatoes and onions that are processed in strict gluten-free processing facilities.

And many Halloween goodies are gluten-free including chocolate kisses, Raisinets, and Jelly Belly jelly beans.

What many gluten-free teens miss is pizza (gluten is in wheat crust).  Many restaurants now offer gluten-free pizza.

Q: Is there a nutritional advantage to eat gluten-free if you do not have a celiac disease or gluten sensitivity?

A: No there is not, says the U.S. Food and Drug Administration.

Q: How do you know you are sensitive to gluten?

A: Blood tests followed up by a biopsy (looking for damage in a piece of your intestines) are the gold standard for diagnosing celiac.

Q: I am writing to you because I have several residents who have celiac disease. I am currently struggling on finding out more about the disease, so I am turning to you for help. Are there any books or reference guides you would suggest to help educate me on the subject? Thank you for your time.

A: Dear K.K. Check out the information on this topic at the National Institutes of Health http://digestive.niddk.nih.gov/ddiseases/pubs/celiac/.

It also lists organizations that can offer expert advice and resource materials.

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