Monster Punch can

An energy drink is a type of drink containing sugar and stimulant compounds, usually caffeine, which is marketed as providing mental and physical stimulation. Energy drinks have the effects caffeine and sugar provide, but there is little or no evidence that the wide variety of other ingredients have any effect. Most effects of energy drinks on cognitive performance, such as increased attention and reaction speed, are primarily due to the presence of caffeine. Other studies ascribe those performance improvements to the effects of the combined ingredients.