Yes, you can feel the difference. I take the liquid vitamin B complex, which I think works better. Not sure about the shot but I know all other B vitamins are water soluble which means that your body does not store it. So it's one of those nutrients that everyone needs to take or get through food everyday. I think a lot of people are actually deficient in the B vitamins and probably other things. Like if you have a thyroid problem but it's not bad enough to get medication, taking kelp/iodine drops will give you energy, if you have problems with anemia sometimes but again it's not so bad to need medical intervention, taking iron and vitamin C will give you energy, or if you have an immune system problem but again without medical intervention, taking L-Lysine will give you energy. But if you're usually pretty healthy but you just feel like you need an energy boost then you probably just need some B vitamins.
at 10:47 AM on Jan. 31, 2011