Thank you to Christine Seivers with Radiology Technician Schools.net who reminded me of this topic. Check out their recent article on diet soda here.
I consider myself to be pretty casual with calorie counting, living by the theory of everything in moderation, but even I have to hesitate at times when it comes to calories, especially with Vermont's latest effort of posting the calorie counts on their menus. (Yikes!) So what better way to deal with the extra calories in alcohol then by mixing it with a diet soda?
In a study performed by Christopher Raynor et al at the Royal Adelaide Hospital in Australia, observed that drinks containing an artificial sweetener had faster gastric emptying times than those that were regularly sweetened. The speed difference was significant with the diet versions emptying 42% faster resulting in quicker times to peak and higher peak blood alcohol concentrations (BAC).
One way to counter this is to add food while consuming your diet cocktails. The presence of food in the stomach, especially fatty food slows alcohol absorption because it slows gastric emptying resulting in a longer time for absorption and lower blood alcohol peak.
Of course then you've just negated the whole point of drinking the diet cocktail in the first place...