I think most people who eat a fairly balanced diet probably get all the vitamins they need. But, I think it is good to take a multivitamin as well to fill in any gaps on a daily basis. It's probably best in the case of the B Complex vitamins, as they are water soluble and you piss them out as the day goes along. This means that a good meal with lots of B Complex in it on one day, will not be retained in your system the next day. So, to keep a good, consistent level of B Complex in your system, daily supplements and/or a multivit are the way to go.