I heard that soda was ok in moderation...?!
Diet soda is quite possible the worst type of soda you can drink, as it contains aspartame (which has been shown to cause brain damage among other diseases). Stick with regular sodas.
If you do feel the need to consume a soft drink, it would be much healthier to have one soda a week, and then drink water the rest of the day to flush it out of your system instead of consuming loads in one sitting.
Drinking water of course is a much better alternative.
soda is loaded with salt.....sodium......bad any way you look at it....