Humectants and dessication, where does the water come from?

[jlarsen]

PG and VG are both humectants, used to moisturize, and also used as dessicants? I'm having trouble wrapping my head around how these substances react with water.

Does vaping dehydrate or hydrate your lungs? Where does the water in the exhaled vapor come from?

Some commercials for ecigs claim that it is "only water vapor". What happens to the vaporized pg/vg? Certainly it isn't completely absorbed by the lungs, so the vapor we exhale must not be water vapor alone. Is the water in the exhaled vapor come from the atmosphere, or is it removed from our bodies, or both?

Thanks.

 

[malyden]

From my understanding the water vapor comes from the moisture in your mouth. vaping will dehydrate your body so you must be careful to drink extra water to prevent you from becoming dehydrated.

 

[Kilroy]

That's the way I understand it as well.

 

[usamare]

When you draw on the e-cig, air and pg are pulled past the heating element. The sudden heating causes the the pg to flash, or rapidly expand. The moisture in the air being drawn through with the pg instantly clings to it, making it both visible and cooler. That's my understanding of it anyway

 

[whiskey]

Thanks for the answers & OP for your question ...I have been curious about this as well...Good Thread!