Here is what I know. Ten years ago, I was rushed to the emergency room with such bad stomach pain, I thought I was loosing my mind. It was worse than child birth, kidney stones, gall bladder..... After 5 different pain medications administered to me in the ER and 16 hours of writhing in pain, one of the nurses asked me if I was a diet soda drinker. When I replied that I was and averaged 1-3 a day, they gave me something and she said that she hoped it was a lesson for me. It took a solid week for me to get rid of the caffeine headaches and total pain. If I do want a soda I'll grab the one with sugar--no more fakes for me.