I noticed a new trend in the energy bars is to add caffeine to them. Everyone has their own opinion, my opinion is that caffeine in general is really bad, adding it to an energy bar is worse.
Most people don't realize that it is actually an addictive drug very similar to cocaine, only not as harmful.
Read for yourself and make your own opinion:
http://home.howstuffworks.com/caffeine.htm
I gave up caffeine about 10 years ago and it was one of the best things I ever did. I sleep better, I need less sleep, I have more energy/stamina, I'm not as moody, my temper doesn't get the best of me...