it has no health benefits. at all. plants don't use it, either. and, you can only eliminate it at a certain rate.
do you know what your body does with the rest of it?
it stores it in your fucking brain.
now, you don't need too much schooling to know that storing metallic ions in your brain is a shit poor idea, all around. you don't want to do that - whether it's mercury, lead, arsenic, cadmium....or aluminum, either.
we don't need hundreds of supplemental studies, we just need to know what your body does with it and realize immediately that that's the worst idea, ever.