Nutrition Fact of the Day: Vitamins themselves provide no usable energy for the body.
Vitamins are a go between energy source. The energy they provide for your body can only be used in chemical reactions. They do not provide you with energy for staying awake, alertness, ect.
So don't be fooled by advertising that states that the energy you receive will be from vitamins and a natural source.
P.S. - I'm referring mostly to energy drinks that say they have no caffeine and no added sugar. And that you will receive your energy from the massive amounts of vitamins they put in it. In fact, it is very harmful to your body if you overdose on too many fat-soluble vitamins.