Soda is bad for you for a variety of reasons, but did you ever think about what it does to your teeth. I recently stumbled across this interesting table from DentalGentleCare.com that shows the acidity of different common beverages.
The reason this is so disheartening is that the PH in our mouth is normally about 6.2 to 7.0 slightly more acidic than water. Therefore, a PH of 5.2 to 5.5 or below the acid begins to dissolve the hard enamel of our teeth. -- Yikes.