Just how harmful are energy drinks mixed with alcohol?

Some researchers are drawing ‘no harm’ conclusions about mixing alcohol with energy drinks even though their research does not reflect real world levels of use, and research funded by a major producer of energy drinks may be confusing the evidence base, suggests a doctor in a personal view published on bmj.com today (10 September).

Mixing alcohol with energy drinks has become popular, but with what risk, asks Peter Miller, Associate Professor of Psychology at Deakin University in Australia.

He says concerns are growing about the harms that may arise from drinkers mixing alcohol and energy drinks which enable them to drink for longer and achieve “higher levels of intoxication”.

He adds that comprehensive data are lacking on energy drinks use by alcohol drinkers in most countries, but in samples, “73% of US and 85% of Italian college students reported consuming energy drinks mixed with alcohol in the past month”.

Studies show that drinkers who consume energy drinks are more likely to record a higher blood alcohol concentration than those who do not and are also more likely to report drinking more alcohol, engaging in aggressive acts, being injured, suffering symptoms of alcohol dependence, having driven while drunk or been the passenger of a drunk driver.

Dr Miller says that the role energy drinks may play is under-researched and much of the research has only studied the effects of combining low levels of alcohol intoxication with a single energy drink.

Some researchers have concluded that “we should not be concerned about the risks”. However, some have been funded by a major producer of energy drinks, Red Bull.

At a 2012 Australasian Professional Society on Alcohol and Drugs conference, 80% of researchers had received financial support from Red Bull and all concluded that no evidence showed that the combination of energy drinks and alcohol increased drinking or chances of harm. Only the independent presenters argued that more research is needed to assess the associations. Dr Miller says only the presenters (who were the first authors of each paper) supplied declarations of competing interest and that these presenters seem to be funded by Red Bull to attend conferences around the world. Dr Miller believes this “inhibit[s] our ability to have a fruitful public health discussion”.

Dr Miller concludes that it is “critical that the public can be confident in the findings of research”. He adds that conference organisers should require researchers working on energy drinks to declare “whether they have received research funding or unrestricted grants, financial support to attend meetings or conferences”.