Final answer:
Energy drinks can contain significantly more caffeine than the FDA allows for soft drinks, as they are considered dietary supplements and are not regulated in the same manner. Caffeine is a central nervous system stimulant that prevents drowsiness by blocking adenosine receptors. However, its excessive consumption can lead to several side effects.
Step-by-step explanation:
Energy drinks often contain a blend of caffeine with other caffeinated substances like guarana and taurine, and they may have significantly more caffeine than the Food and Drug Administration (FDA) allows for soft drinks. This is because energy drinks are considered dietary supplements, which are not regulated by the FDA in the same way as food.
Caffeine is a central nervous system stimulant and the most widely consumed psychoactive drug. It works primarily by blocking the action of adenosine on its receptors, keeping you alert and delaying the onset of drowsiness. However, excessive consumption can cause side effects such as sleep disruption, shakiness, anxiety, and even insomnia. While "normal" consumption might not be harmful to most people, the higher caffeine content in energy drinks compared to soft drinks can be a concern, especially since the exact amounts can vary widely between products.