An individual’s breath alcohol concentration (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 non-alcoholic 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.
“More attention needs to be paid to how alcohol is being
consumed in the ‘real world,’” said Cecile A. Marczinski, assistant professor
of psychology at Northern Kentucky University. She referenced an earlier field
study of bar patrons. “Researchers found that, one, individuals who reported
consuming alcohol with diet beverages had the highest BrACs, as compared to all
other bar patrons, and two, that women tended to be more frequent consumers of
diet mixers with their alcohol. These good naturalistic observations give
researchers many ideas to explore in a controlled laboratory setting.”
“I am really interested in drinking and driving as a
problem, so I wanted to know if the simple choice of mixer could be the factor
that puts a person above or below the legal limit,” added Marczinski. “I also
wanted to determine if any BrAC difference would be something that subjects
would notice, since this has implications for safe drinking practices,
including decisions to drive.”
Study authors 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 Marczinski. “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.”
When asked why mixing alcohol with a diet drink appears to
elevate BrACs, the researchers 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.”
The researchers 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.”
“Research on alcohol mixers is critically important for
improving serving practices in on-premise drinking establishments,” he said.
“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.”
“We have an obesity crisis in this country,” added
Marczinski. “As such, individuals tend to be conscious about how many calories
they are consuming, and they might think that mixing alcohol with diet drinks
is a healthy choice. Yet the average reader needs to know that while mixing
alcohol with a diet beverage mixer may limit the amount of calories being
consumed, higher BrACs are a much more significant health risk than a few extra
calories.”
In natural drinking settings, such as bars and nightclubs,
young women are significantly more likely than young men to order drinks mixed
with diet cola. This occurs because young women tend to be more weight
conscious than young men. Thus, from a public health perspective, artificially
sweetened alcohol mixers may place young women at greater risk for a range of
problems associated with acute alcohol intoxication.
