Are there different levels of celiac disease? Is it like lactose intolerant where you can have milk cooked into something but you can't drink a glass of milk straight?.
For real Celiacs, not much. In some, parts per million can affect them. Some of them get the rash from hell when they ingest any gluten at all.
That's why it annoys so many, because if they aren't worried about cross contamination... it's not Celiac. And so many never get tested. They take a protein out of their diet based on a guess (which is generally wrong) and once you take it out of your diet it's difficult to put back in. In fact, some who have taken it out of their diet find out that they get the rash from hell if they try to start eating it again... they essentially develop the autoimmune disease because they took it out of their diet.
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