Acute effects of consumption of energy drink on intraocular pressure and blood pressure-pilot study

Abstract

Context: Energy drinks are popular caffeinated beverages believed to improve cognitive function and concentration. They contain two main ingredients taurine and caffeine, which have both been reported to have effects on blood pressure (BP) and intraocular pressure (IOP). Aim: The aim of this study is to investigate the acute effects of consumption of energy drinks on IOP and BP of healthy black young subjects. Materials and Methods: A total of 50 undergraduates from the University of Benin, Nigeria, aged 18-30 years (mean 24.43 ± 1.54) were randomly selected to participate in this study. The subjects were of either gender and were divided into experimental and control groups of 25 subjects each. The subjects were told to abstain from caffeine for 48 h prior to and during the study. Baseline IOP and BP were measured. The experimental group consumed one can of Red Bull (containing 85 mg of caffeine in 250 ml) and measurements were repeated at 30, 60 and 90 min while the control group drank 250 ml of water and were tested over the same period of time. Results: When compared to baseline, a significant decrease in mean IOP was observed at 30, 60 and 90 min ( P P > 0.05). Conclusion: Results suggest that energy drinks produce a significant reduction in IOP, but have no effect on blood pressure. These findings may however reflect the combined effect of caffeine and taurine, as present in Red Bull.