A cup of coffee may make it harder for people to realise they’re drunk, according to new lab research.
Besides, popular caffeinated “alcohol-energy” drinks don’t neutralise alcohol intoxication, findings from a mouse study suggest.
“The myth about coffee’s sobering powers is particularly important to debunk because the co-use of caffeine and alcohol could actually lead to poor decisions with disastrous outcomes,” said co-author Thomas Gould of Temple University.
“People who have consumed only alcohol, who feel tired and intoxicated, may be more likely to acknowledge that they are drunk,” he added.
“Conversely, people who have consumed both alcohol and caffeine may feel awake and competent enough to handle potentially harmful situations, such as driving while intoxicated or placing themselves in dangerous social situations.”
In the lab, caffeine made mice more alert but did not reverse the learning problems caused by alcohol, including their ability to avoid things they should have known could hurt them.
Scientists gave groups of young adult mice various doses, both separately and together, of caffeine and of ethanol (pure alcohol) at levels known to induce intoxication.
The doses of caffeine were the equivalent of up to six or eight cups of coffee for humans. Control mice were given saline solution.
Gould and co-author Danielle Gulick, then tested three key aspects of behaviour: the ability to learn which part of a maze to avoid after exposure to a bright light or loud sound; anxiety, reflected by time spent exploring the maze’s open areas; and general locomotion.
Ethanol, as expected, increased locomotion and reduced anxiety and learning in proportion to the dose given, says a Temple release.
In other words, intoxicated animals were more relaxed and moved around more but learned significantly less well than control mice to avoid the part of the maze with the unpleasant stimuli.
These findings were published in Behavioural Neuroscience.
