Brief Answer:
Not just water vapor

Detailed Answer:
Hello

Thanks for the query

Nicotine and tar free hookahs are relatively safer option than the regular Hookahs however it is not completely free of side effects. It is because of the following reasons

1. Hookahs contain charcoal, charcoal when burned releases carbon monoxide. Carbon monoxide is readily absorbed and it is also known to be carcinogenic
2. It also releases another compound called polyaromatic hydrocarbon which is unhealthy as well
3. One recent study found that in a typical hookah smoking session, participants inhaled more carbon monoxide than someone who smokes a pack or more a day of conventional cigarettes
4. It leads to long term side effects like chronic obstructive pulmonary disease

I strongly advice you against smoking of any form of Hookah

I wish you good health

Regards

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