Ive heard this from differant sources at differant times, but its rubbish.

They make up science stuff about fluoride binding and breaking down molecules to an active substance or some crap.

It's all just a trick to get stupid naieve kids to do something disgusting.
SAme as smoking banana skins or peanut shells.

It's like making virus' that effect normal peoples personal computers, its just for the sake of being malicious and knowing that somehwere out their because of you someone is suffering.

It's a load of crap and tastes foul (I was told!!! I tried nutmeg as a young teenager years ago but thats IT.)