Not only have energy drinks become increasingly popular among adolescents and young adults in recent years, so too has mixing and drinking them with alcohol. However, research on the subjective psychological, physiological, and behavioral risk-taking outcomes of alcohol/energy drinks has had mixed results. A first-of-its-kind study compares the outcomes of alcohol/energy drinks with alcohol-only drinks among members of the Australian public.
Results will be published in the November 2012 issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.
"The majority of previous research regarding energy drink and alcohol/energy drink consumption rates has been restricted to American, Canadian, and European regional college student or community samples," said Amy Peacock, a doctoral candidate in the school of psychology at the University of Tasmania as well as corresponding author for the study. "Yet a similar problem is evident in Australia. This is the first Australian research regarding the frequency of energy drink and alcohol/energy drink use in a community sample."
Prior to this study, explained Peacock, the primary source of data regarding the consumption of energy drinks and alcohol/energy drinks were sales figures. "The data suggest that the sales of energy drinks have increased exponentially in the last few years," she said. "However, while we can access data regarding caffeinated alcoholic beverage sales, the very nature of alcohol/energy drinks, the mixing of two separate beverages, makes sales estimates quite difficult, particularly in non-licensed venues."
Peacock and her colleagues collected data from 403 Australians (159 males, 244 females), 18 to 35 years of age, who completed a 10- to 30-minute online survey between May and June 2011. All participants had consumed alcohol/energy and alcohol-only drinks in the preceding six months, and retrospectively responded to questions regarding the occurrence of 17 physiological and 21 mood states as well as 26 risk behaviors in drinking sessions during the preceding six months when they had consumed alcohol/energy drinks versus alcohol only.
"Alcohol-energy drink consumers were less likely to experience several psychological and physiological sedation side-effects, such as speech and walking difficulties, nausea, slurred speech, confusion, and exhaustion, when drinking alcohol/energy drinks compared to alcohol," said Peacock. "However, they also had a greater chance in alcohol/energy drink sessions of experiencing several side-effects related to over-stimulation, including heart palpitations, increased speech speed, sleeping difficulties, agitation and tremors, jolt and crash episodes, and irritability and tension."
"The reported side-effects of energy drink/alcohol consumption are similar to those reported by consumers of caffeine," said Andrea Carr, associate lecturer in psychology at the University of Tasmania. "To avoid these, consumers of energy drinks alone or combined with alcohol should be aware of the caffeine content of their drinks and any additional caffeine that they may have consumed that will contribute to an exacerbation of these effects."
"While alcohol/energy drink consumers reported risk-taking during both alcohol and alcohol/energy drink sessions," noted Peacock, "they had lower odds of engaging in a range of risk behaviours such as driving while intoxicated, having casual sex, using illicit drugs, gambling, engaging in physical or verbal aggression, and being injured, losing consciousness, or requiring medical treatment when under the influence of alcohol/energy drinks." Both Peacock and Carr found this to be inconsistent with existing research.
"While this pattern of results was evident consistently across all 26 assessed risk behaviours," cautioned Peacock, "we would not encourage any hasty conclusions regarding the causal relationship between alcohol/energy drinks and risk-taking. Instead, we hope that the present results will encourage further research in this area, particularly experimental research involving the objective measurement of risk-taking post- alcohol/energy drink consumption."
"Findings also indicate that more than half of the energy drink/alcohol consumers surveyed reported exceeding the Australian National Health and Medical Research Council's recommended intake of alcohol, namely five or more standard alcoholic drinks in any given session," said Carr. "This pattern of behaviour is somewhat concerning."
Peacock agreed. "This finding raises serious concern regarding the general alcohol consumption habits of alcohol/energy drink consumers," she said. "In comparison, data from the 2010 Australian National Drug Strategy Household Survey revealed that approximately one-quarter or 28 percent of the Australian population aged 14 years or older were consuming alcohol at this level on at least a monthly basis."
Peacock added that it is important to consider energy drinks separate from their advertising. "Energy drinks are commonly associated with sport, masculinity, and risk-taking via marketing strategies," she said. "While energy drinks may potentially provide increased alertness and reduced fatigue, they do not offer additional protection from the negative outcomes of risk-taking."