Prenatal vitamins & nail, hair, and skin. Dangerous Iron levels? Take every two days?

I'm a young woman, 19. I have a... somewhat poor diet due to funds, somewhat average weight, and tall height stature, if that matters or counts at all in this situation-- just giving the details. So I've heard about the wonders of prenatal vitamins, and I've heard the horror stories as well when it comes to taking them when you aren't trying to conceive, or just not pregnant period. From what I've read, it seems as if taking prenatal vitamins when you aren't pregnant either works great, or it is a complete disaster, depending on who you ask. I understand that taking prenatals is for the intent on getting *extra* nutrients for the growing baby. This of course pumps lots of extra iron into you. Great for a baby, bad for someone who isn't pregnant. So what I was thinking, should taking *half* of a pill every day even that out? Or take a whole pill, and just skip a day after? Has anyone else tried this? Has it worked for you personally?