KatieAnn Skogsberg (below) assistant professor of psychology and behavioural neuroscience, led a student research team at Kentucky-based Centre College to complete this study, and told BeverageDaily.com yesterday that she was surprised by the lack of scientific attention devoted to the lucrative US energy drinks industry.
Skogsberg said her team found many studies on the effects of caffeine on brain activity and reaction time in the research literature, but none on energy drinks or shots, with publications in this space treating how participants reported feeling – as opposed to recording objective measures.
Discussing the preliminary study’s eye-catching results, unveiled at a recent poster presentation, Skogsberg nonetheless urged caution: “This is a preliminary study using a small sample size, so the first and most important step is to replicate it, using more participants, and even have more labs replicate our research. We need more research, more ‘takes’ on it,” she said.
‘We cannot comment on the student research’: 5-Hour Energy
Elaine Lutz, from 5-Hour Energy’s distributor Living Essentials LLC, responded thus, telling BeverageDaily.com: “We cannot comment on the student research, since we, like you, have not seen the unpublished small sample research in full, its methodology or what peer review process the research may or may not have undergone.”
And Lutz cited a randomized, double-blind, placebo-controlled crossover scientific study subject to Institutional Review Board (IRB) review, showing that 5-Hour Energy increased alertness and cognitive function in a group consuming the supplement over a five-hour plus period, versus a control group given a placebo.
After being prompted by her husband, who asked her whether energy drinks really worked, Skogsberg said she and her team decided to test the effects of 5-Hour Energy’s ‘energy blend’ (vitamins B6, B12, Niacin, Folic Acid, Tyrosine, Taurine) using electroencephalographic (EEG) equipment to measure brainwave activity.
Double-blind study measures P300 brainwave
Accordingly, the scientists designed a double-blind study to measure levels of a specific brain wave involved in decision making called ‘P300’, to find out if energy drinks improve reaction times better than caffeine alone.
Skogsberg described P300 as “the workhorse of visual attention research”, and said it was used to recognize a stimulus deemed to be rare and particularly meaningful (Luck 2005).
Ruijter, Loris, Snel & Ruiter (2000) found that fatigued subjects produced a larger P300 after consuming caffeine compared to a placebo, suggesting caffeine increased arousal levels and the ability to recognize and respond to the stimulus.
“It’s been used quite a bit in other studies looking at caffeine, as an indicator showing that caffeine does increase arousal and alertness levels,” Skogsberg said, since P300 activity increased in magnitude after intake.
The team pursued the following research question: “Does the energy blend contained in energy drinks improve a person’s P300 amplitude and latency time on visual attention tasks compared to caffeine alone?”
31 Centre College undergraduate students were screened for skin, caffeine and artificial sweetener sensitivities, along with vision and attention disorders, prior caffeine consumption and sleep history.
Undergraduates completed an attention task (clicking a computer mouse button when a certain letter appeared onscreen) after drinking either water, water with caffeine, or water with 5-Hour Energy.
Flavor, artificial color and artificial sweeteners were controlled by the team, and in the experiment P300 brainwaves were measured for 30 minutes using an electroencephalogram (EEG) cap.
Looking at other energy drink brands
Initial results showed that students drinking caffeinated drinks had faster brain responses as against the placebo (water), but there was no difference between those who drank caffeine versus 5-Hour Energy.
Thus Skogsberg’s team concluded that the 5-Hour Energy blend does not significantly improve performance any more than caffeine alone, and said further work directions would involve investigating placebo effects.
Skogsberg said her research team was already working to design additional experiments – involving alternative energy drink brands – and preparing a manuscript for publication based on their preliminary results.
“We’re collecting the data, replicating the experiment (since in science you must be careful) and might add the placebo aspect to it before we publish. It just depends on how much excitement there is,” she said.
Title: ‘The Effect of Energy Drinks on Visual Attention Task Performance’
Authors: Benham, C., Oberst, L., Rose, G., Blaine, L., Stevenson, K., Skogsberg, K.A.
Source: Unpublished poster presentation (Centre College student research project), presented at the Annual Meeting of the Association for Psychological Science, Washington D.C