some thoughts stemmed from this article.
Diet Coke as with all fizzy drinks have a unique taste and sensory properties.
As humans, once we like it, we are getting used to these sensory properties because our mind remembers the pleasure (hedonic score it is called in Sensory Science), and we are seeking this pleasure day in day out.
For coke, though, things are a bit more complicated.
From a food science point of you, we don't know the exact composition of coke since this is an in-house secret recipe that has been kept in house since coke was "invented".
Coke contains caffeine and a cola extract.
Both are addictive!
Caffeine is a powerful alkaloid that it is highly addictive.
However, there are alternatives to break the bad habit of drinking coke.
The people (like the one on the Irish Times story) need to seek an alternative source of caffeine and here Food Science can help them. Coffee and Tea contain caffeine and these two drinks can act as substitutes for caffeine. We need to highlight here that coffee and tea are much more healthy than diet coke or coke.
Therefore, there is a way to break the vicious cycle of addiction to Coke.
One more thing: the artificial sweeteners that "sugar-free" drinks contain are usually aspartame and another one.
Aspartame is a toxic sweetener and we need to keep an eye on humans' intake of this compound.