This might sound kind of strange, but I wonder if I would eat always perfectly and then one day I would eat eg chocolate cake, would my body say I am not use to all this junk I will make you sick.
A lot of things I eat right mainly organic, but I also want to go off it once in awhile so my body will learn to accept everything.
I know this a simple thought, but we always have to be carefull with anything not to go overboard.
You have to keep your immune system working too.