Are there razor blades in it? Cyanide? If not, drinking Sprite or any other soft drink on occasion will not make you healthier, but it is only detrimental to your teeth (carbonation and sugar). If abused, then you can get a whole bunch of other problems, just like you would anything else that is abused. Weight gain, diabetes, etc. could be promoted via this type of "pop ingestion".
So if you enjoy a Sprite, drink it, just keep in mind that, with anything we enjoy, moderation is essential.