Every healthy drink is the same, every unhealthy drink is unhealthy in its own way. That's my conclusion upon analyzing this data set containing nutrition info of Starbucks drinks from the data set aggregator Factual.
It turns out that there's an inverse, non-linear relationship between the sodium and sugar content of a drink. Drinks with very little sodium tend to have lots of sugar. These are mainly things like lemonade and iced tea. (Of course, it's controversial whether salt is bad for you, but the prevailing evidence points to yes.)
|normalized to the number of calories, filtered for >50 calories only; code|
Surely this is not a universal trade-off, but it seems to indicate that in order to survive as a popular drink, you have to offer consumers something that they'll enjoy.