As sorority girls have suspected for years, researchers have now found that using diet soda as a mixer with alcohol can dramatically increase levels of intoxication.
In a study published in the Alcoholism: Clinical and Experimental Research, researchers tested which compared Smirnoff Red Label plus Squirt (a lemon-lime soda that is caffeine free) with with Diet Squirt mixed with vodka. They found that the diet cocktail increased BAC (that would be breath alcohol content, not blood alcohol content) by 18%. 18% is a lot, almost as much as another drink. In some cases, this amount caused people to be over the legal driving limit.
The study involved 16 young men and women who self-identified as social drinkers. They were tested three different times and were given either a placebo, a diet Squirt with Smirnoff or a full-sugar Squirt with Smirnoff. Researchers wanted to use the caffeine-free Squirt because caffeine can affect whether or not people think they are intoxicated, although it doesn’t affect the levels of alcohol in your breath. They also made sure that each dose of vodka was specifically suited to each participant’s weight and gender, in order to put them close to the .08 legal limit for drinking.
After drinking the cocktails, participants had to accomplish a number of tasks, including a test for their reaction time and a computer task. According to TIME,
At all times, the amount of alcohol measured in the volunteers’ breath was higher among those whose cocktails included diet drinks.
Cecile Marczinski, the study’s lead author, said:
One of the key things we found was that even though BAC peaked 18% higher in the diet condition, [participants] didn’t feel any more intoxicated and they didn’t feel any different as to how willing they were to drive a car.
So why does diet soda tend to make people more intoxicated? Researchers speculate that it has to do with the chemical content of the soda: because it’s less sugary, the body doesn’t work as hard to digest it, thus making it enter the bloodstream more quickly. Marczinski said: “The stomach doesn’t recognize that it needs to do anything with that drink, because it has no sugar. It goes right to [the] small intestine where the most alcohol is absorbed into the bloodstream.” Interesting, right? Common drinking knowledge says avoid sugary drinks because they make hangovers worse, but this data says that they can actually help your body better digest the alcohol you’ve pounded.
The results of this study have the potential to really change the way people drink. Sadly, I doubt most people will read it and say “Ok, no more Diet Coke with my rum…it’s regular Coke now!” but I hope that, over time, this information can be disseminated and become common knowledge. It’s something that could be very valuable for certain categories of drinkers, including women and dieters (who might more often order diet soda as a mixer because of the lower calorie content) and college students. There is, of course, the possibility that the data from this study can be abused (WOOHOO! Diet soda gets you drunker faster!) but hopefully the benefit to this knowledge will ultimately outweigh the negatives.