how do they do fake smoking in movies?

[Gripper]

They hold dry ice in their mouths and blow that out

Hold dry ice in your mouth ? It would burn you, it's like -20°C or smth

Rodding in movie world

[twisterX]

dry ice if you hold it in your hand for like a few secs you get like frostbite.

You need like a special glove to hold it. I wouldnt want to lose my tounge for a movie.

[DarthInsinuate]

is that a rod after the admission of a rod? that's good, that's very good