What can happen when you have taken much more than the normal amounts of vitamins?

Your body can either ignore the nutrients or reject them.

You can get sick from certain vitamins because your body wont be able to digest all of them, causing negative affects on your organs.

You can also just have nothing negative happen. For example, taking an extremely high dose of vitamin D3 would most likely not hurt you, however after a certain point you would not gain anything from it.