Yes... . Soda pop contains corrosive acids such as citric, malic, tartaric carbonic or phosphoric which, can remove calcium from tooth enamel. Without protection from the dental enamel, the tissue underneath is susceptible to cavities, root canals & even extractions. Sugar is an additional cavity causing issue, so consider rinsing your mouth after drinking diet soda & soda containing sugar. Water is best.
Depends. Depends on what you will replace it with. Water is always the best drink.