For the 6-year programs it is (obviously) a bit of overkill, since they accept people directly out of high school.
For the 4/5-year graduate programs, it can't hurt... but the only way to get each school's take on that is to contact the schools themselves. Their individual criteria (and value on a graduate degree) could vary considerably. It's certainly worth emailing/calling all of the schools on your list.
BA - Oregon °°° MS - BYU °°° MD - MU-Sofia
"When I haven't any blue... I use red."
- Pablo Picasso
"Aren't you glad you went through all those years of medical school... so you could work like a secretary with all of these patient records?"
- M.M., Urology Nurse