Why not? No real reason other than a novelty and it's easier to get the dried-on mucus off in the morning or the rare occasion when I'm sick.
It's also easier to get popcorn kernels unstuck from my back of my throat when that happens and easier to extract tonsil stones without using my finger or a different oral tool.
Also, as I've replied to other comments, I've got a slightly higher mucus production than most people seem to naturally have. So it helps to not have to blow my nose as often.
I've seen people in videos online that could do it. I'm not there yet and I'm not sure I ever will or really want to be. It'd be a neat party trick if I could.
Imagine if someone with a bifurcated tongue did it and had one coming out of each nostril.
Your mileage may vary for sure. I naturally produce more mucas than most people, but not an obscene amount or anything. I don't remember it ever starting to hurt after I did it unless I ate acidic or spicy food recently though.
Doing it gradually is the best approach. I built up to 2.5 after a few months of just messing around. It never really gave me a headache that I can recall, but I don't get headaches very often either.
I've never given myself a sinus infection in the 10 years I've been doing this, but others might?
I naturally produce more mucus than most people anyway. I'm not really sure, maybe it's minor dust allergies? It generally makes things easier for me to manage.
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