Alcohol + diet drinks elevate intoxication more than alcohol + regular drinks
Washington, February 6: Mixing alcohol with a diet soft drink can result in a higher breath alcohol concentration (BrAC) than mixing alcohol with a regular or sugar-sweetened drink, according to a new study.
An individual's BrAC following alcohol intake is influenced by several factors, including food. While it is known that food delays the stomach emptying, thus reducing BrAC, only recently has the role of nonalcoholic drink mixers used with alcohol been explored as a factor influencing BrAC.
A new comparison of BrACs of alcohol consumed with an artificial sweetener versus alcohol consumed with a sugared beverage has found that mixing alcohol with a diet soft drink can result in a higher BrAC.
Researchers had 16 participants (8 females, 8 males) attend three sessions where they received one of three doses � 1.97 ml/kg vodka mixed with 3.94 ml/kg Squirt, 1.97 ml/kg vodka mixed with 3.94 ml/kg diet Squirt, and a placebo beverage � in random order.
The participants' BrACs were recorded, as well as their self-reported ratings of subjective intoxication, fatigue, impairment, and willingness to drive. Their objective performance was assessed using a cued go/no-go reaction time task.
"Alcohol consumed with a diet mixer results in higher BrACs as compared to the same amount of alcohol consumed with a sugar-sweetened mixer," said Cecile A. Marczinski, assistant professor of psychology at Northern Kentucky University.
"The subjects were unaware of this difference, as measured by various subjective ratings including feelings of intoxication, impairment, and willingness to drive. Moreover, their behavior was more impaired when subjects consumed the diet mixer," Marczinski noted.
When asked why mixing alcohol with a diet drink appears to elevate BrACs, Dennis L. Thombs, professor and chair of the department of behavioral and community health at UNT Health Science Center, explained that the stomach seems to treat sugar-sweetened beverages like food, which delays the stomach from emptying.
"The best way to think about these effects is that sugar-sweetened alcohol mixers slow down the absorption of alcohol into bloodstream. Artificially sweetened alcohol mixers do not really elevate alcohol intoxication. Rather, the lack of sugar simply allows the rate of alcohol absorption to occur without hindrance," he said.
Both Marczinski and Thombs were concerned about the risk that diet mixers can pose for alcohol-impaired driving.
"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," Marczinski added.
Results will be published in the April 2013 issue of Alcoholism: Clinical and Experimental Research and are currently available at Early View.