all the old pops were named after ingredients. Coca-cola had cocaine, Pepsi had pepsin, Dr. Pepper had peppermint, ginger ale had ginger, root beer was made from a root, etc. Coke just had the worst ingredient lol. but if I recall right, several pops were intended as more medicinal or something....I don't really know though.
and anything is unhealthy if you have too much of it.
one thing I've noticed though. if you go awhile without drinking Pepsi, Coke tastes good but then Pepsi doesn't. same thing with Coke if you go awhile without drinking it and then drink Pepsi, the Pepsi tastes better.

I wonder if there's some ingredient that make you dislike the other?