Many times you must have observed some sort of fuzzy substance stuck in your belly button. The term is belly button lint, my friend. But why it is caused and why only near the belly button.
Well the credit goes to research done by Austrian chemist Georg Steinhauser.
As per him, firstly, the hairs around the navel have very minute scales that act a bit like hooks that latch onto clothe fibers.
Then secondly, those hairs tend to grow in circular patterns around the belly button, leading to the optimize the collection.
However some also think that rubbing of navel hairs and clothing contributes to a build-up of static electricity, resulting in the collection of clothing fibers and to a lesser extent, dead skin cell. But no solid grounds for that yet.