I've attempted to drink normal sugar-filled soft drinks and felt terrible after a few days. That's based on 3 cans a day. The amount of sugar is just too much for me to handle.
I can drink water, but it is quite boring. I actually find drinking just water stops quenching my thirst and my mouth dries out progressively. Drinking fruit juice is also not going to work as it is very acidic, and I just can't handle more than a couple of glasses.
A mix of these drinks is fine, but not ideal. I just want a constant I can drink without preparatiog.
Diet soda fits all the criteria for me. It has a taste, unlike water, contains caffeine (diet coke is my poison), and rehydrates. I can also drink it all day without any real side-effects. The downside being the aspartame and phenylalnine it contains which may or may not be an issue depending on what you read.
I do limit myself to 3 cans per day, but then aspartame is contained in other things I consume every day. The most frequent of which is sugar free gum.
If there are any alternatives to aspartame-using diet drinks, sugar filled drinks, or just plain water I should be trying I'd appreciate some suggestions.