Diet Mixers Will Make You More Intoxicated Than Using Regular Soft Drinks
February 6, 2013

Diet Mixers Will Make You More Intoxicated Than Using Regular Soft Drinks

Lawrence LeBlond for - Your Universe Online

When it comes to cocktails and other mixed drinks, a new study has found that using diet soft drinks as mixers can be making people more drunk than using regular sugary beverages. In one of the first-of-its-kind studies, researchers tested the effects that mixing sweet and non-sweetened soft drinks with alcohol has on breath-alcohol concentration (BrAC).

The study suggests that women are most at risk of getting more drunk (by as much as 20 percent), because they tend to be the ones who go for the diet soda most often when mixing drinks. This behavior is most likely associated with women who are keener on watching their waistlines.

While the study, to be published in the April 2013 issue of Alcoholism: Clinical & Experimental Research, only included a small set of individuals–eight men and eight women–the results were pretty impressive.

A team of researchers, led by Cecile Marczinski of Northern Kentucky University (NKU), asked participants to come to the research lab on two separate days to test the effects of mixing sweet and non-sweetened beverages with alcohol.

During the first visit, the researchers gave the participants a vodka drink with a diet mixer and observed as they became intoxicated. On the next visit, the researchers offered the same drink, only this time mixed with a sugary beverage. During both visits, the mixed drinks had the potency of about four mixed drinks, ensuring the dose would produce favorable results for the team, as it has been shown in past studies that this amount is enough to raise the blood-alcohol level to the legal driving limit.

The researchers discovered that when drinking the sugar-free concoction, the participants became more intoxicated more quickly than when drinking the sugary mixed drink. And not only did they become drunk faster, but the sugar-free concoction sent them over the legal driving limit, whereas the sugary drink did not.

Surprisingly, the participants reported that they did not feel any more inebriated on the sugar-free version than they did on the sugary drink, and were just as likely to think they were sober enough to get behind the wheel.

"What you choose to mix your alcohol with could possibly be the difference between breaking or not breaking the law," said Marczinski, assistant professor in the Department of Psychological Science at NKU.

The team used breath tests to monitor the BrAC levels in the participants. They also had them complete computer tasks to test their reaction times, mimicking what they might face while driving. Those drinking the diet concoction were slower to respond. The team said they would have had to add at least one more sugary drink mix to get participants to the same level they were at on the diet concoction.

This research follows evidence from another study that measured alcohol levels in people leaving bars and night clubs. In that study, researchers asked if patrons had either drank cocktails mixed with regular soft drinks or with diet sodas. That research showed similar results, maintaining that sugared cocktails slow down the absorption of alcohol into the bloodstream.

"Marczinski's findings are very consistent with what we've found in the field in a natural drinking environment. When the mixer is diet soda, the bar patrons tend to have somewhat higher intoxication levels than when they consume regular soda," said Dennis Thombs, professor and chair of the Department of Behavioral and Community Health, School of Public Health at the University of North Texas in Fort Worth, author of the night club study.

People often mix their alcohol with diet soda to cut down the calories. And women are more often the ones performing this than men. But Marczinski said it isn´t worth the risk. “It's much more harmful to the brain, to your liver, if you have a higher blood alcohol level. A few extra calories is not going to make that much difference (in your weight).”

In her study, participants using the diet mixture only reduced calorie intake by 130.

People may believe they are doing themselves a favor when they use diet mixers with their alcohol, but it could be far from the truth, according to Marczinski and Thombs.

"In this study, subjects felt the same whether they drank the diet or regular mixed alcoholic beverage," said Marczinski. "However, they were above the limit of .08 when they consumed the diet mixer, and below it when they drank the regular mixed beverage. Choices to drink and drive, or engage in any other risky behavior, often depend on how people feel, rather than some objective measurement of impairment. Now alcohol researchers who are interested in prevention have something new to consider when developing or modifying intervention programs."

"Research on alcohol mixers is critically important for improving serving practices in on-premise drinking establishments," added Thombs. "About one-half of all drinking and driving incidents are estimated to occur in persons leaving these settings. This type of research can provide guidance to policy-makers interested in improving the safety of bars and nightclubs."

Perhaps the big question is: why do people get more intoxicated when they go for diet mixers instead of regular soft drinks? The answer lies with digestion. Diet soda allows the alcohol to pass more quickly through the stomach, offering alcohol a faster route to the bloodstream.

But with regular soda, the stomach treats it as food and slows digestion down to a crawl, delaying the time it takes for alcohol to poison the bloodstream, spreading it out over a longer period of time.

"I think the takeaway from this study is, don't trust your judgment about intoxication levels, you may be off," said Marczinski. "And many times people think they're safe to drive and they are in fact not."

Update (Feb. 6, 2013  3:05 p.m.):

The American Beverage Association (ABA) had the following to say in response to the BrAC paper appearing in the journal Alcoholism: Clinical & Experimental Research:

“This paper, which looks at only 16 people, does not show that mixing diet soft drinks with alcohol causes increased intoxication. Rather, it simply supports the long known fact that consuming calories - from any food or beverage - along with alcohol slows down its impact."

"If the study participants consumed alcohol with any other non-caloric beverage, including water or even club soda, the results would be the same. Most importantly, consumers need to be aware of the effects of alcohol itself — regardless of whether or not they consume it together with anything else," concluded the statement.