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The response to that question has been overwhelmingly in favor of the problem being Aspartame, the sweetener used in the Diet Coke. I have experimented since I originally posted, and I agree that it was probably the Aspartame that gave me diarrhea.
OK, does anybody know of sodas that don't use Aspartame in the diet drinks. I know of Coke and Faygo.
Susan, OH
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