@Charlotte, everything supposedly causes cancer now a days. Try not to worry about things like that. Worry about things you can prevent. :0) I know it don't answer your question but I hope it was encouraging or helpful to you. :0)
Diet coke has not been proven to cause cancer. This was an allegation made by the Centers for Science in the Public Interest, which used rodents in doing the studies. However, the Food and Drug Administration states that there is no proof of increased risks in human.
Anything with diet in it has this weird long ingredient that's like phykfsccrdazsfgturr ( not that but some crazy word that's hard to pronounce) and that ingredient it terrible for you. It would be better to drink the non diet stuff even thought with calories. Other foods that have that Ingredient in them is most gum fake sugar like Splenda and fruit water (that new drink )diet drinks. My BFFs grandfather died like 7 years ago and he had some type of cancer die to having Splenda. I'm sure there's more to his death but that was one of the reasons