Sugar-free cocktails get you drunk faster, new research suggests. Photo credit: Getty Images.

Diet soda and booze could make a volatile mix, according to a University of Kentucky researcher.

"Mixing your alcoholic beverage with a sugar-free soda will make you feel drunker, faster," said Cecile A. Marczinski, an assistant professor of psychology at the university who studies the effects of alcohol.

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In one of her recent studies, Marczinski gave 16 volunteers vodka mixed with regular soda, diet soda or a placebo over the course of three separate drinking sessions. When the subjects guzzled the sugar-free cocktails, their breath alcohol levels were on average 18 percent higher than when they downed the full-calorie mixers, the results showed. Their reaction times were also slower and they had trouble judging how drunk they truly were.

The reason you get tipsy faster sipping diet cocktails is because regular soda contains sugar, which the body treats as food, Marczinski said,

"Your stomach empties more slowly with sugar in your system but when there is no sugar, the alcohol goes directly into your blood stream," she said. "Drinking alcohol without any mixer probably would have the same effect as no sugar."

If you're watching your weight - as nearly 40 percent of Americans resolve to do each January, according to the Journal of Clinical Psychology - it's especially important to watch what you drink too. Many people may mistakenly believe that shaving a few calories off their adult beverage is a smart choice when in reality they could be harming their health, Marczinski said.

"We know that higher alcohol levels are dangerous to your brain and liver, so keeping your alcohol levels in the moderate range should be more important than trying to save 100 or so calories," she said.

And calorie-counting women should be especially careful, Marczinski pointed out, since they are generally smaller, metabolize alcohol faster than men, and are more sensitive to alcohol-related diseases.

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