MONDAY, May 22, 2006 (HealthDay News) -- Saving calories by blending your liquor with a "diet" mixer sounds like a good idea, but new research finds it might also make you drunker, sooner.
The mixer switch might even be enough to make you a dangerous driver.
"Drinking diet versus regular [mixers] could put you in trouble in the eyes of the law," said Dr. Chris Rayner, a researcher at the Royal Adelaide Hospital in Adelaide, Australia, who presented the data.
His team reported their findings Monday at the annual Digestive Disease Week meeting in Los Angeles.
In the study, Rayner and his colleagues tracked the blood-alcohol levels of eight men. On two different days, the men drank either an orange-flavored vodka beverage made with a regular mixer (478 calories) or a diet mixer (225 calories). In each case, the vodka included 30 grams of ethanol [alcohol] in a 600 milliliter serving.
Sugar content is important to how quickly alcohol enters the system, Rayner explained.
"Caloric load influences how quickly the stomach is emptied," he said, with lower-calorie beverages emptying more quickly than regular mixers. He theorized that drinks made with diet mixers would make it into the digestive system more rapidly.
To test that theory, Rayner's team used ultrasound to calculate rates of gastric emptying after the men drank each of the beverages. They also sampled the participants' blood-alcohol level just after drinking and up to 3 hours after consumption.
As expected, the diet drinks emptied from the stomach faster than drinks made with regular mixers. And about 30 minutes after drinking, the blood-alcohol levels peaked for both types of drinks. But there was a catch: That peak averaged 0.05 percent for men consuming alcohol with diet mixers, compared to just 0.03 percent for men quaffing the regular drinks.
"The time point at which the peak alcohol [effect] occurred was similar," Rayner said, but "the magnitude of the peak varied greatly."
In most states, the current legal blood-alcohol limit for operating a motor vehicle is 0.08 percent for drivers ages 21 and above, according to the U.S. Centers for Disease Control and Prevention.
Dr. Lee Kaplan, director of the Massachusetts General Hospital Weight Center and moderator of the panel, cautioned that the study included only men and that men and women metabolize alcohol differently. He said a study of any diet mixer's effects should be done with women as subjects, as well.
Women achieve higher concentrations of alcohol in the blood than men do with equivalent amounts and become more intoxicated, according to the U.S. National Institutes of Health.
To learn more about alcohol, visit the U.S. Centers for Disease Control and Prevention.