Question: Do I need to avoid products that state 'may contain' the food I am allergic to or 'processed in a plant' that makes this food?
Answer: I'd say yes, because there's the potential for contamination. If it's still processed in the same plant, there are some good examples of that in history where -- for example, the classic is that the plain M&Ms were processed in a factory where peanut M&Ms were also made. My understanding is that no longer occurs, but that's one way that plain M&Ms historically caused peanut allergic reactions in some peanut allergic people.
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