Unfounded? I don't thinkso. For starters the sweeteners in diet coke are already linked with brain cancer...Coca-Cola and Pepsi are changing the recipes for their drinks to avoid putting a cancer warning label on the bottle, to comply with California laws.
The new recipe for caramel colouring in the drinks has less 4-methylimidazole - a chemical which California has added to its list of carcinogens.
The change to the recipe has already been introduced in California.
But the companies say rolling out the new recipe across the US makes the drinks more efficient to manufacture.
"While we believe that there is no public health risk that justifies any such change, we did ask our caramel suppliers to take this step so that our products would not be subject to the requirement of a scientifically unfounded warning," Coca-Cola representative Diana Garza-Ciarlante told the Associated Press news agency.
BBC News - Coke and Pepsi alter recipe to avoid cancer warning label