Everyone in this thread except for Ced is wrong. To clarify:
Energy drinks are the fucking worst thing for your body. They are one of those things where in ten years scientists are gonna come out with some article like "Hey... not the best idea... fuck... mad cancer..." or something. Energy drinks are. Fortunately, Five Hour is not an energy drink.
Now, this doesn't mean you should be downing this shit like orange juice. However, whoever said these are ridiculously bad for you is actually retarded. Look at the ingredients. ONE CUP OF COFFEE worth of caffeine, and tons of B Vitamins. Yeah, the excessive amount of B Vitamins isn't great for you, but it beats the living FUCK out of taurine, guarana, and excessive caffeine counts. By a lot. Plus you don't feel like shit after an hour. So... yeah. If you're gonna buy, buy Five Hour.