Other popular sodas like Diet Coke and Dr Pepper include quite a bit less caffeine compared to Mountain Dew Zero Sugar too, with 46 and 41 milligrams in a 12-ounce can respectively.

I'm a diet soda (and, really, diet beverage) hound, so I have had one too many run-ins with caffeine-free Diet Coke over the years. Diet Coke, specifically, is like kryptonite for me.