Well, if you learn a lot about celiac disease, you must go to a especially sensitive med school. Yes I had a biopsy to confirm the disorder. However, there is debate about whether that is necessary if there is a positive blood test.

Perna was right about the issue around oats. Most oats are cross contaminated in growing, transporting, or processing. There are some brands that are certified gluten free because they control for these things and then test to make sure there is no gluten contamination. The problem is that some people react to oats because the protein in oats is similar enough to the ones in the others. The other thing is that the certified gluten free oats (along with other specialty gluten free food) is very expensive. A box of gluten free rice pasta is $4-5. The hardest thing is the cost of being gluten free. I avoid traveling and eating out because of the risk of cross contamination.

You would NOT die if you had to stop eating rye bread. It is comments like this that are very insensitive. You would adjust.