It turns out that your insides are not, in fact, your insides. The gastrointestinal tract is a great big tube full of the external environment. Sure, it passes through you, but from the in-hole to the out-hole, your body is busy squishing, mashing, mixing and digesting foreign substances – absorbing some and protecting itself from others. We are well set-up to soak up the bits we need. We have even invited some special guests to help break down things we can’t handle. These little bugs munch on stuff and let off gas. And so do we.
What do I mean about the external environment? Try thinking of it this way: Imagine it is the early nineteen eighties and you, your three kids, your sister and a cousin are crammed onto a small fishing boat with forty other refugees, heading to Australia. Pirates board the vessel and so as not to lose the last trace of your husband, you grit your teeth and swallow your wedding ring. Where is it now?
You swallow the ring and it’s inside you, but it never enters your bloodstream. It’s not going to lodge in your heart or shoot off down to your big toe. It won’t become a part of you. It’s in a tube, and it’s going to come out in your poo.