An overload of iron in the blood is called hemochromatosis, and can be fatal if it's not diagnosed. Basically what it does is rusts out your organs. It's more common in Europeans and is caused by a hereditary gene, so it's good to know if it runs in your family or not. It's referred to as the "Bronze Killer" because it has a tendancy to turn a person a bronzy tanned colour, weird eh? Anyway, if it's diagnosed it can easily be treated by having blood drawn (phlebotomies or something, I can't remember if that's the correct word for it) depending on just how high your levels are. Some people have to have them weekly, some monthly, etc.
I don't know if people are routinely checked for this in Europe, it's not really something that a lot of people know about, but if it runs in your family it's good to get everyone DNA tested to find out if they're a carrier or if they have the disease because if it turns non-dormant, you'll have to do something to control it. Also, then you can pass the information down to the next person so their doctor can be on the lookout for it showing up.
Edit - Sorry, I didn't click on the link a few posts above me. Everything is explained there. Carry on!