ABSTRACT
Aims: Proton magnetic resonance spectroscopy (MRS) is an imaging technique that provides noninvasive, in-vivo measurement of brain biochemistry. The objective of this study was to explore the effects of a commercial energy drink (ED) on brain metabolites in adult males using MRS. Methods: Ten males (18 to 30 years), of mean body mass index 23.8±2.2 kg/m2 [range 21.4-27.8 kg/m2] were recruited and randomized to either the intervention group (n=5) or control group (n=5). The intervention group were asked to consume two 250ml cans of Red Bull and the control group consumed no drink. One dimensional MRS on a 1.5T Achieva MRI scanner was obtained of bioccipital gray matter. Subjects were placed in the scanner and a spectrum acquired every 5.75 minutes for 60 minutes. Linear mixed models were generated to determine the main effects due to differences between groups and times and the interaction. Results: There was a significant group by time effect for N-acetylaspartate (NAA) (P= .02, d= 0.7) and a statistical trend for macromolecule 20 (MM20) (P= .06 d= 0.1) with the control group having higher concentrations than that of the intervention. Mean differences from baseline to 45 minutes for NAA in the intervention group were -0.8 mM (-12%) compared with 0.15 mM (<1%) for control and for MM20 -0.12 mM (<1%) in the intervention group compared with 0.03 mM (<1%) for control. Conclusions: Consumption of two cans of ED was found to produce few changes in brain metabolites with moderate effect sizes. Changes detected in this study demonstrate the sensitivity of the MRS method to explore nutrition related variables with 1.5T clinical MRI unit. The study provides some insight into an understudied, topical area of research.