What groups of people would be looking to lower their iron intake?

Iron overload: Folks with hereditary hemochromatosis, if not treated by phlebotomy, store too much of the iron in their food and eventually get sick and die as a result. However, dietary restriction is basically futile and having the iron removed by taking off a pint of blood every few weeks easy and works -- so well that there's no reason to forego enjoying a nice steak.